Image processing system, external device, and image processing method

ABSTRACT

An image processing system includes an external device including an orientation specifying unit that specifies orientation of the body-insertable apparatus, a rotation correcting unit that aligns orientations of a plurality of pieces of image data, a screen generating unit that generates a screen displaying the image data, an average color bar generating unit that calculates an average color of the image data, generates an image of the calculated average color, and generates an average color bar in which images of the generated average colors are connected, and an organ image generating unit that generates an organ image, obtained by superimposing the images of the average colors generated by the average color bar generating unit. The screen generating unit generates the screen in which the average color bar generated by the average color bar generating unit is incorporated, and incorporates the organ image into the screen.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 12/879,402filed on Sep. 10, 2010 which is a continuation of PCT internationalapplication Ser. No. PCT/JP2010/050556 filed on Jan. 19, 2010 whichdesignates the United States, incorporated herein by reference, andwhich claims the benefit of priority from Japanese Patent ApplicationsNo. 2009-058657, filed on Mar. 11, 2009, incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image processing system, an externaldevice, and an image processing method. More particularly, the inventionrelates to an image processing system having a body-insertable apparatushaving imaging means, an external device, and an image processingmethod.

2. Description of the Related Art

Devices for observing the inside of a subject such as a human being oran animal include a tube-type endoscope and a capsule-type endoscope(hereinbelow, simply called a capsule endoscope). The tube-typeendoscope includes an electronic endoscope whose tip is provided with aCharge Coupled Device (CCD) sensor and a fiber scope in which a bundleof optical fibers is inserted in a tube, and obtains images of theinside of a subject by inserting the tube from the mouse, the anus, orthe like of the subject. On the other hand, the capsule endoscope has asize that a human, an animal, or the like can swallow the capsuleendoscope. For example, the capsule endoscope is introduced orally tothe inside of a subject and periodically captures images of the insideof the subject. The images of the inside of the subject captured aretransmitted as wireless signals to an external receiving device. Theobserver individually or continuously reproduces a plurality of imagesobtained by the tube-type endoscope or the capsule endoscope andobserves the images, thereby diagnosing the inside of the subject.

SUMMARY OF THE INVENTION

An image processing system according to an aspect of the presentinvention includes a body-insertable apparatus including an imaging unitthat captures inside of a subject and an output unit that outputs imagedata obtained by the imaging unit to the outside; and an external deviceincluding an input unit that receives the image data, a firstorientation specifying unit that specifies orientation of thebody-insertable apparatus at the time of capturing the image data withrespect to a reference direction, a rotation correcting unit thatperforms rotation correction on image data which is received by theinput unit based on the orientation specified by the first orientationspecifying unit, thereby aligning orientations of a plurality of piecesof image data, a screen generating unit that generates a screendisplaying the image data subjected to the rotation correction in therotation correcting unit, an average color bar generating unit thatcalculates an average color of the image data subjected to the rotationcorrection in the rotation correcting unit, generates an image of thecalculated average color, and generates an average color bar in whichimages of the generated average colors are connected in accordance withorder of the image data, and an organ image generating unit thatgenerates an organ image, as an image of an organ in the subject,obtained by superimposing the images of the average colors generated bythe average color bar generating unit, wherein the screen generatingunit generates the screen in which the average color bar generated bythe average color bar generating unit is incorporated, and incorporatesthe organ image generated by the organ image generating unit into thescreen.

An image processing system according to another aspect of the presentinvention includes a body-insertable apparatus including an imaging unitthat captures inside of a subject and an output unit that outputs imagedata obtained by the imaging unit to the outside; and an external deviceincluding an input unit that receives the image data, a firstorientation specifying unit that specifies orientation of thebody-insertable apparatus at the time of capturing the image data withrespect to a reference direction, a rotation correcting unit thatperforms rotation correction on image data which is received by theinput unit based on the orientation specified by the first orientationspecifying unit, thereby aligning orientations of a plurality of piecesof image data, a screen generating unit that generates a screendisplaying the image data subjected to the rotation correction in therotation correcting unit, and a rotation amount image generating unitthat generates a rotation amount image visually displaying a rotationamount used for the rotation correction for each of the image data,wherein the screen generating unit generates the screen in which therotation amount image generated by the rotation amount image generatingunit is incorporated.

An external device according to still another aspect of the presentinvention includes an input unit that receives image data obtained by abody-insertable apparatus including an imaging unit that captures insideof a subject; an orientation specifying unit that specifies orientationof the body-insertable apparatus at the time of capturing the image datawith respect to a reference direction; a rotation correcting unit thatperforms rotation correction on image data which is received by theinput unit based on the orientation specified by the orientationspecifying unit, thereby aligning orientations of a plurality of piecesof image data; a screen generating unit that generates a screendisplaying the image data subjected to the rotation correction in therotation correcting unit; an average color bar generating unit thatcalculates an average color of the image data subjected to the rotationcorrection in the rotation correcting unit, generates an image of thecalculated average color, and generates an average color bar in whichimages of the generated average colors are connected in accordance withorder of the image data; and an organ image generating unit thatgenerates an organ image, as an image of an organ in the subject,obtained by superimposing the images of the average colors generated bythe average color bar generating unit, wherein the screen generatingunit generates the screen in which the average color bar generated bythe average color bar generating unit is incorporated, and incorporatesthe organ image generated by the organ image generating unit in thescreen.

An external device according to still another aspect of the presentinvention includes an input unit that receives image data obtained by abody-insertable apparatus including an imaging unit that captures insideof a subject; an orientation specifying unit that specifies orientationof the body-insertable apparatus at the time of capturing the image datawith respect to a reference direction; a rotation correcting unit thatperforms rotation correction on image data which is received by theinput unit on the basis of the orientation specified by the orientationspecifying unit, thereby aligning orientations of a plurality of piecesof image data; a screen generating unit that generates a screendisplaying the image data subjected to the rotation correction in therotation correcting unit; and a rotation amount image generating unitthat generates a rotation amount image visually displaying a rotationamount used for the rotation correction for each of the image data,wherein the screen generating unit generates the screen in which therotation amount image generated by the rotation amount image generatingunit is incorporated.

An image processing method according to still another aspect of thepresent invention includes receiving image data obtained by abody-insertable apparatus including an imaging unit that captures insideof a subject; specifying orientation of the body-insertable apparatus atthe time of capturing the image data with respect to a referencedirection; performing rotation correction on the image data based on thespecified orientation, thereby aligning orientations of a plurality ofpieces of image data; generating a screen displaying the image datasubjected to the rotation correction; calculating an average color ofthe image data subjected to the rotation correction, generating an imageof the calculated average color, and generating an average color bar inwhich images of the generated average colors are connected in accordancewith order of the image data; and generating an organ image, as an imageof an organ in the subject, obtained by superimposing the images of theaverage colors generated at the generating the average color bar,wherein the generating the screen, includes generating the screen inwhich the generated average color bar is incorporated, and incorporatingthe generated organ image.

An image processing method according to still another aspect of thepresent invention includes receiving image data obtained by abody-insertable apparatus including an imaging unit that captures insideof a subject; specifying orientation of the body-insertable apparatus atthe time of capturing the image data with respect to a referencedirection; performing rotation correction on image data which isreceived by the input unit on the basis of the specified orientation,thereby aligning orientations of a plurality of pieces of image data;generating a screen displaying the image data subjected to the rotationcorrection; and generating a rotation amount image visually displaying arotation amount used for the rotation correction for each of the imagedata, wherein the generating the screen includes generating the screenin which the generated rotation amount image is incorporated.

An image processing system according to still another aspect of thepresent invention includes a body-insertable apparatus including animaging means for capturing inside of a subject and an output means foroutputting image data obtained by the imaging unit to the outside; andan external device including an input means for receiving the imagedata, an orientation specifying means for specifying orientation of thebody-insertable apparatus at the time of capturing the image data withrespect to a reference direction, a rotation correcting means forperforming rotation correction on image data which is received by theinput means based on the orientation specified by the orientationspecifying means, thereby aligning orientations of a plurality of piecesof image data, a screen generating means for generating a screendisplaying the image data subjected to the rotation correction by therotation correcting means, an average color bar generating means forcalculating an average color of the image data subjected to the rotationcorrection by the rotation correcting means, generating an image of thecalculated average color, and generating an average color bar in whichimages of the generated average colors are connected in accordance withorder of the image data, and an organ image generating means forgenerating an organ image, as an image of an organ in the subject,obtained by superimposing the images of the average colors generated bythe average color bar generating means, wherein the screen generatingmeans generates the screen in which the average color bar generated bythe average color bar generating means is incorporated, and incorporatesthe organ image generated by the organ image generating means into thescreen.

An image processing system according to still another aspect of thepresent invention includes a body-insertable apparatus including animaging means for capturing inside of a subject and an output means foroutputting image data obtained by the imaging means to the outside; andan external device including an input means for receiving the imagedata, an orientation specifying means for specifying orientation of thebody-insertable apparatus at the time of capturing g the image data withrespect to a reference direction, a rotation correcting means forperforming rotation correction on image data received by the input meansbased on the orientation specified by the orientation specifying means,thereby aligning orientations of a plurality of pieces of image data, ascreen generating means for generating a screen displaying the imagedata subjected to the rotation correction in the rotation correctingmeans, and a rotation amount image generating means for generating arotation amount image visually displaying a rotation amount used for therotation correction for each of the image data, wherein the screengenerating means generates the screen in which the rotation amount imagegenerated by the rotation amount image generating means is incorporated.

The above and other features, advantages and technical and industrialsignificance of this invention will be better understood by reading thefollowing detailed description of presently preferred embodiments of theinvention, when considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing a schematic configuration of amedical system according to a first embodiment;

FIG. 2 is a block diagram showing a schematic internal configuration ofa capsule medical device according to the first embodiment;

FIG. 3 is a perspective view illustrating schematic appearance of thecapsule medical device according to the first embodiment;

FIG. 4 is a cross section showing a sectional structure when the capsulemedical device is cut in a plane including an imaging plane of a CCDarray in an imaging unit according to the first embodiment;

FIG. 5 is a block diagram showing an example of a schematicconfiguration of a receiving device according to the first embodiment;

FIG. 6 is a diagram showing an example of arrangement of antennas on thereceiving device side according to the first embodiment;

FIG. 7 is a block diagram showing an example of a schematicconfiguration of a display device according to the first embodiment;

FIG. 8 is a diagram illustrating an example of a GUI screen generatedaccording to the first embodiment;

FIG. 9 is a diagram showing successive image data obtained by imagingthe same region in a subject by the capsule medical device in the firstembodiment;

FIG. 10 is a diagram showing an example of an average color bargenerated according to the first embodiment;

FIG. 11 is a flowchart showing an example of outline operation of thecapsule medical device according to the first embodiment;

FIG. 12 is a flowchart showing an example of outline operation of thereceiving device according to the first embodiment;

FIG. 13 is a flowchart showing an example of outline operation of thedisplay device according to the first embodiment;

FIG. 14 is a diagram for explaining correction of rotation of image datain step S123 in FIG. 13;

FIG. 15 is a diagram showing an example of an average color bargenerated by using image data after the rotation correction in step S127in FIG. 13;

FIG. 16 is a schematic diagram showing a schematic configuration of amedical system according to modification 1-1 of the first embodiment;

FIG. 17 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 1-1 of the first embodiment;

FIG. 18 is a flowchart showing an example of outline operation of thereceiving device according to the modification 1-1 of the firstembodiment;

FIG. 19 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to anotherexample of the modification 1-1 of the first embodiment;

FIG. 20 is a schematic diagram showing a schematic configuration of amedical system according to modification 1-2 of the first embodiment;

FIG. 21 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 1-2 of the first embodiment;

FIG. 22 is a flowchart showing an example of outline operation of thecapsule medical device according to the modification 1-2 of the firstembodiment;

FIG. 23 is a flowchart showing an example of outline operation of thereceiving device according to the modification 1-2 of the firstembodiment;

FIG. 24 is a schematic diagram showing a schematic configuration of amedical system according to a second embodiment;

FIG. 25 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to the secondembodiment;

FIG. 26 is a flowchart showing an example (No. 1) of outline operationof the capsule medical device according to the second embodiment;

FIG. 27 is a flowchart showing an example (No. 2) of outline operationof the capsule medical device according to the second embodiment;

FIG. 28 is a flowchart showing an example of outline operation of thereceiving device according to the second embodiment;

FIG. 29 is a schematic diagram showing a schematic configuration of amedical system according to modification 2-1 of the second embodiment;

FIG. 30 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 2-1 of the second embodiment;

FIG. 31 is a flowchart showing an example of outline operation of thecapsule medical device according to the modification 2-1 of the secondembodiment;

FIG. 32 is a flowchart showing an example of outline operation of thereceiving device according to the modification 2-1 of the secondembodiment;

FIG. 33 is a schematic diagram showing a schematic configuration of amedical system according to modification 2-2 of the second embodiment;

FIG. 34 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 2-2 of the second embodiment;

FIG. 35 is a flowchart showing an example of outline operation of thereceiving device according to the modification 2-2 of the secondembodiment;

FIG. 36 is a schematic diagram showing a schematic configuration of amedical system according to a third embodiment;

FIG. 37 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to the thirdembodiment;

FIG. 38 is a diagram for explaining rotation correction according to thethird embodiment;

FIG. 39 is a diagram showing an example of an average color bargenerated by using image data subjected to rotation correction accordingto the third embodiment;

FIG. 40 is a schematic diagram showing a schematic configuration of amedical system according to modification 3-1 of the third embodiment;

FIG. 41 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 3-1 of the third embodiment;

FIG. 42 is a schematic diagram showing a schematic configuration of amedical system according to modification 3-2 of the third embodiment;

FIG. 43 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 3-2 of the third embodiment;

FIG. 44 is a schematic diagram showing a schematic configuration of amedical system according to a fourth embodiment;

FIG. 45 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to the fourthembodiment;

FIG. 46 is a schematic diagram showing a schematic configuration of amedical system according to modification 4-1 of the fourth embodiment;

FIG. 47 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 4-1 of the fourth embodiment;

FIG. 48 is a schematic diagram showing a schematic configuration of amedical system according to modification 4-2 of the fourth embodiment;

FIG. 49 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to themodification 4-2 of the fourth embodiment;

FIG. 50 is a schematic diagram showing a schematic configuration of amedical system according to a fifth embodiment;

FIG. 51 is a block diagram showing a schematic configuration example ofa capsule medical device and a receiving device according to the fifthembodiment;

FIG. 52 is a flowchart showing a schematic configuration example of thecapsule medical device according to the fifth embodiment;

FIG. 53 is a flowchart showing an example of outline operation of thereceiving device according to the fifth embodiment;

FIG. 54 is a block diagram showing an example of a schematicconfiguration of a display device according to a sixth embodiment;

FIG. 55 is a flowchart showing an example of outline operation of thedisplay device according to the sixth embodiment;

FIG. 56 is a diagram showing an example of a GUI screen generated by ascreen generating unit according to the sixth embodiment;

FIG. 57 is a diagram showing an example of an average color baraccording to modification 6-1 of the sixth embodiment;

FIG. 58 is a diagram showing an example of an average color baraccording to modification 6-2 of the sixth embodiment;

FIG. 59 is a diagram showing an example of an average color baraccording to modification 6-3 of the sixth embodiment;

FIG. 60 is a block diagram showing an example of a schematicconfiguration of a display device according to a seventh embodiment;

FIG. 61 is a flowchart showing an example of outline operation of thedisplay device according to the seventh embodiment;

FIG. 62 is a diagram showing an example of a GUI screen generated by ascreen generating unit according to the seventh embodiment;

FIG. 63 is a diagram showing an example of an average color baraccording to modification 7-1 of the seventh embodiment;

FIG. 64 is a diagram showing an example of a GUI screen according to aneighth embodiment;

FIG. 65 is a diagram showing the relation between a region in a lumenthrough which a capsule medical device introduced in a subject passesand rotation amount;

FIG. 66 is a block diagram showing an example of a schematicconfiguration of a display device according to modification 8-1 of aneighth embodiment;

FIG. 67 is a diagram showing an example of a GUI screen according tomodification 8-2 of the eighth embodiment;

FIG. 68 is a diagram showing an example of a GUI screen according tomodification 8-3 of the eighth embodiment;

FIG. 69 is a block diagram showing an example of a schematicconfiguration of an image selecting unit according to a ninthembodiment;

FIG. 70 is a diagram showing an example of a GUI screen according to atenth embodiment;

FIG. 71 is a block diagram showing an example of a schematicconfiguration of a display device according to an eleventh embodiment;

FIG. 72 is a block diagram showing an example of a schematicconfiguration of a display device according to a twelfth embodiment; and

FIG. 73 is a diagram showing an example of a GUI screen according to thetwelfth embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Best modes for carrying out the present invention will be described indetail below with reference to the drawings. In the followingdescription, the drawings just schematically show shapes, sizes, andpositional relations to a degree that the content of the presentinvention can be understood. Therefore, the present invention is notlimited only to the shapes, sizes, and positional relations shown in thedrawings. In the drawings, to clearly show the configuration, a part ofhatching in cross sections is omitted.

First Embodiment

In the following, the configuration and operation of a medical system 1according to a first embodiment of the invention will be described indetail below with reference to the drawings. In the first embodiment,the case of using a capsule body-insertable apparatus (hereinbelow,called capsule medical device) 10 introduced in a subject 900 orally andcapturing images of the inside of the subject 900 by executing imagingoperation while traveling in a lumen 902 (refer to FIG. 1) from thestomach to the anus of the subject 900 will be described as an example.The invention, however, is not limited to the case but can be variouslymodified to, for example, the case of using a capsule medical devicefloating in liquid stored in a stomach, small intestine, largeintestine, or the like of the subject 900 and the case of using acapsule medical device introduced by applying a magnetic field from theoutside of the body to a magnet fixed in the capsule medical device.

Configuration

FIG. 1 is a schematic diagram showing a schematic configuration of themedical system 1 according to the first embodiment. As illustrated inFIG. 1, the medical system 1 has the capsule medical device 10introduced in the subject 900, for example, via the oral route, areceiving device 130 for transmitting/receiving image data, a controlinstruction, and the like to/from the capsule medical device 10 byperforming wireless communication with the capsule medical device 10,and a display device 150 for executing predetermined process on theimage data received from the capsule medical device 10 by the receivingdevice 130 and displaying the processed image data to the observer. Thereceiving device 130 and the display device 150 are external devicesdisposed on the outside of the subject 900.

To the receiving device 130, a portable recording medium 140 such as aflash memory (registered trademark) or a smart card (registeredtrademark) can be inserted. In the portable recording medium 140, forexample, image data and the like received from the capsule medicaldevice 10 is stored. The observer moves the portable recording medium140 from the receiving device 130 to the display device 150 and executesa predetermined process such as a process of reproducing image datastored in the portable recording medium 140 or a converting process byusing the display device 150. As the display device 150, an informationprocessor such as a personal computer or a workstation, a display suchas a liquid crystal display or an organic EL display can be used.

Capsule Medical Device

An example of the schematic configuration of the capsule medical device10 is shown in FIGS. 2 to 4. FIG. 2 is a block diagram showing aschematic internal configuration of the capsule medical device 10. FIG.3 is a perspective view showing a schematic appearance of the capsulemedical device 10. FIG. 4 is a cross section showing a sectionalstructure when the capsule medical device 10 is cut in a plane includingan imaging plane of a CCD array 11 a in an imaging unit 11.

As shown in FIG. 2, the capsule medical device 10 has: the imaging unit11 for illuminating and imaging the inside of the subject 900, aprocessing unit 12 for executing a process on an image generated by theimaging unit 11 and other various processes, a memory unit 13 forstoring the image data and the like processed by the processing unit 12,a transmitting/receiving unit 14 and an antenna 15 a fortransmitting/receiving a signal to/from the receiving device 130, andone or more batteries 16 for supplying power to the inside of thecapsule medical device 10.

The imaging unit 11, the processing unit 12, the memory unit 13, thetransmitting/receiving unit 14, and the battery 16 are housed in awater-tight casing 18 made by a container 18 a and a cap 18 b. As shownin FIG. 3, one end of the container 18 a has a hemispherical dome shapeand the other end has an almost cylindrical shape or a semiellipticalshape which is open. On the other hand, the cap 18 b has a hemisphericalshape and is fit in the opening of the container 18 a, therebywater-tightly sealing the casing 18. At least the cap 18 b is made oftransparent resin or the like.

The imaging unit 11 is imaging means for imaging the inside of thesubject 900 and includes an LED 11 c for illuminating the inside of thesubject 900, a CCD array 11 a in which Charge Coupled Devices (CCDs) aslight emitting elements are arranged in a matrix, an objective lens 11 bdisposed on the light reception face side of the CCD array 11 a, and adrive circuit (not shown) for driving the LED 11 c and a drive circuit(not shown) for driving the CCD array 11 a. The imaging unit 11periodically operates (for example, twice per second), thereby imagingthe inside of the subject 900 and generating image data. The generatedimage data is read by the drive circuit and supplied to the processingunit 12 in an almost real-time manner.

The processing unit 12 executes predetermined signal process on inputimage data and supplies the processed image data to thetransmitting/receiving unit 14. The transmitting/receiving unit 14mainly functions as output means for outputting image data captured bythe imaging unit 11 to the receiving device 130 on the outside.Therefore, the image data subjected to the predetermined signal processby the processing unit 12 is transmitted by radio in an almost real-timemanner from the transmitting/receiving unit 14 to the receiving device130 via the antenna 15 a. The invention, however, is not limited to thecase. Image data subjected to the predetermined image signal process maybe stored in the memory unit 13 and, after the capsule medical device 10is taken from the subject 900, the image data may be taken from thememory unit 13. Preferably, to the transmitted/stored image data, forexample, a time stamp is added by the processing unit 12 so that imagingtime, imaging timing, and the like are known.

As shown in FIGS. 1, 3, and 4, the LED 11 c and the CCD array 11 a aredisposed in the casing 18 so that an illuminating/imaging direction Dris directed to the outside of the casing 18 via the transparent cap 18b. The CCD array 11 a is disposed in an almost center in a sectionperpendicular to the longitudinal direction of the casing 18. On theother hand, a plurality of LEDs 11 c are disposed point-symmetrical orline-symmetrical so as to surround the CCD array 11 a in the section. Inthe first embodiment, a direction in a plane parallel to the lightreception face of the CCD array 11 a is set as a specified direction Uiof the capsule medical device 10. For clarification of explanation, acertain direction is set to a direction which passes through the centerC of the light reception face of the CCD array 11 a and is an upwarddirection on a screen in the case of displaying an image generated bythe CCD array 11 a as it is on, for example, the display device 150.Therefore, in the invention, in the case of displaying image data readfrom the CCD array 11 a as it is on the display device 150, thespecified direction Ui and the upward direction Du on the screen (referto FIG. 8) coincide with each other.

As the antenna 15 a of the capsule medical device 10, for example, anantenna having directivity is used. In the first embodiment, a loopantenna is used as the antenna 15 a. However, the invention is notlimited to the loop antenna. Any antenna is applicable as long as it candetect the direction of the antenna 15 a with respect to a reference (inthe first embodiment, as an example, a direction connecting the head andthe foot of the subject 900, in the following, called a referencedirection Ds) on the basis of the phase, strength, or the like in anantenna 120 as an observation point, of an electromagnetic wave(hereinbelow, including electric wave) generated from the antenna 15 aof the capsule medical device 10 as a signal source.

The antenna 15 a having the directivity is fixed on the inside of thecasing 18. The antenna 15 a is fixed in the casing 18 so that the centerline of the loop of the antenna 15 a (corresponding to the symmetricalaxis of an electric field distribution shape of the electromagnetic wavegenerated by the antenna 15 a) and the longitudinal direction of thecapsule medical device 10 do not become parallel to each other.Consequently, even in the case where the capsule medical device 10rotates using the center line in the longitudinal direction as an axis,the orientation of the specified direction Ui of the capsule medicaldevice 10 with respect to the reference direction Ds can be specified onthe basis of the phase, strength, or the like of the electromagneticwave in a plurality of observation points in the receiving device 130.

Preferably, the orientation of the center line of the antenna 15 ahaving directivity is made coincide with the orientation of thespecified direction Ui. Since the orientation of the reference directionDs of the antenna 15 a can be used directly as the orientation withrespect to the reference direction Ds of the specified direction Ui, theprocess in the receiving device 130 which will be described later can belessened.

Receiving Device

As shown in FIGS. 1 and 6, image data transmitted by radio from thecapsule medical device 10 is received by a plurality of antennas 120 ato 120 i (hereinbelow, reference numeral of arbitrary one of theantennas 120 a to 120 i will be set as 120) disposed on the surface ofthe subject 900 and input to the receiving device 130 disposed on theoutside of the subject 900 via a cable 121. An example of a schematicconfiguration of the receiving device 130 according to the firstembodiment is shown in the block diagram of FIG. 5.

As shown in FIG. 5, the receiving device 130 has atransmitting/receiving circuit 131 for transmitting/receiving a signalto/from the capsule medical device 10 via the antenna 120, a signalprocessing circuit 132 for executing a predetermined process on thesignal (particularly, image data) input from the transmitting/receivingcircuit 131, a memory 134 for storing the image data or the likesubjected to the predetermined process, and an operation unit 135 and adisplay unit 136 realizing the Graphical User Interface (GUI) functionfor making the observer enter various operations and instructions to thecapsule medical device 10 and the receiving device 130. Thetransmitting/receiving circuit 131 also has a function of phasedetecting means which detects the phase in each of the antennas 120 a to120 i, of an electromagnetic wave transmitted from the antenna 15 a ofthe capsule medical device 10. The transmitting/receiving circuit 131also has, as strength detecting means detecting strength in each of theantennas 120 a to 120 i, of the electromagnetic wave transmitted fromthe antenna 15 a of the capsule medical device 10, for example, aReceived Signal Strength Indicator (RSSI) circuit 131 a for detectingstrength of the electromagnetic wave received in each of the antennas120. That is, the transmitting/receiving circuit 131 also functions asstrength/phase detecting means detecting strength and phase in each ofthe antennas 120 a to 120 i, of the electromagnetic wave transmittedfrom the antenna 15 a of the capsule medical device 10.

The receiving device 130 also has a CPU 133 functioning as orientationspecifying means estimating spatial spread (electric field distribution)of the electromagnetic wave from the phase of the electromagnetic wavein each of the antennas 120 detected by the transmitting/receivingcircuit 131 and the strength in each of the antennas 120 detected by theRSSI circuit 131 a and specifying orientation with respect to thereference direction Ds of the antenna 15 a of the capsule medical device10 (that is, orientation with respect to the reference direction Ds ofthe specified direction Ui).

In the first embodiment, the antenna 15 a of the capsule medical device10 functions as a signal source generating a sign (electromagnetic wavein the example) for orientation detection for specifying the orientationof the capsule medical device 10 (that is, tilt of the specifieddirection Ui) with respect to the reference direction Ds, the antenna120 functions as an observation point for observing the sign(electromagnetic wave) for orientation detection generated from thesignal source (antenna 15 a), and the CPU 133 of the receiving device130 functions as orientation specifying means specifying the orientationof the capsule medical device 10 (that is, tilt of the specifieddirection Ui) with respect to the reference direction Ds from thestrength and phase of the sign (electromagnetic wave) for orientationdetection observed at the observation point (antenna 120). Forspecification of the orientation of the capsule medical device 10 usingthe electromagnetic wave, for example, convergence calculation byiterative operation using the least square method.

The plurality of antennas 120 a to 120 i are, for example, dipoleantennas, loop antennas, or the like and are fixed to a jacket 122 thesubject 900 can wear as shown in FIG. 6. The number of antennas 120, anarrangement pattern, and an object to which the antennas 120 are fixedare not limited to those shown in FIG. 6 but can be variously modifiedas long as the number and the arrangement pattern by which the CPU 133can estimate/specify the spatial spread (electric field distribution) ofthe electromagnetic wave (sign for orientation detection) emitted fromthe antenna 15 a of the capsule medical device 10 as a signal source onthe basis of the strength, phase, and the like of the electromagneticwave (sign for orientation detection) observed at the antenna 120 as anobservation point and the fixation object which can be substantiallyfixed to the subject 900 are used. In the description, the number of theantennas 120 is at least two.

The information of the orientation (hereinbelow, called orientationdata) with respect to the reference direction Ds of the specifieddirection Ui specified by the CPU 133 is temporarily stored inassociation with image data received simultaneously or around the sametime from the capsule medical device 10 into the memory 134. The memory134 functions as a buffer temporarily storing image data.

After that, the image data and the orientation data stored in the memory134 is either accumulated in the portable recording medium 140 via aninterface (I/F) 137 or transmitted from the interface (I/F) 137 to thedisplay device 150 via a communication cable 159 in an almost real-timemanner. The interface 137 can be variously changed according to the datainput/output method such as a Universal Serial Bus (USB) interface or acommunication interface used for Local Area Network (LAN) or the like.

Display Device

As described above, the display device 150 is constructed by aninformation processor such as a personal computer or a workstation or adisplay such as a liquid crystal display or an organic EL display. Asshown in FIGS. 1 and 7, the display device 150 has a control unit 151for controlling operations and input/output of data in the displaydevice 150, a memory unit 153 for temporarily storing image data andorientation data or the like input from an interface unit 152 via theportable recording medium 140 or the communication cable 159, an imageprocessing unit 154 for executing a predetermined process on input imagedata and generating a screen provided to the observer, a display unit155 for displaying the screen generated by the image processing unit154, and an input unit 156 with which the observer enters variousinstructions on the basis of the screen displayed on the display unit155. FIG. 7 is a block diagram showing a schematic configuration exampleof the display device 150 according to the first embodiment.

The interface unit 152 functions as input means that enters image data(including orientation data) from the capsule medical device 10 via thereceiving device 130. The image data and the orientation data enteredfrom the interface unit 152 is temporarily stored in the memory unit 153via the control unit 151. After that, the image data and the orientationdata is properly input to the image processing unit 154 and is subjectedto a predetermined process. The processed image data may be stored againin, for example, the memory unit 153.

The image processing unit 154 executes a predetermined process whichwill be described later on the input image data and the orientation dataand, after that, generates a GUI screen to be provided for the observerby using the processed image data. The GUI screen generated is suppliedto the display unit 155 via the control unit 151 and displayed on thedisplay unit 155. The display unit 155 and the input unit 156 providethe GUI function using the GUI screen being displayed to the observer.The observer selects a target function by inputting variously operationsfrom the input unit 156 such as a mouse and a keyboard, anddisplays/reproduces a desired image on the display unit 155. Theobserver reads a displayed/reproduced image, thereby diagnosing theinside of the subject 900.

The image processing unit 154 will be described more specifically. Asshown in FIG. 7, the image processing unit 154 includes a rotationcorrecting unit 154 a for rotation-correcting image data, a featurepoint extracting unit 154 b for extracting a feature point of imagedata, an image selecting unit 154 c for selecting image data on thebasis of the feature point extracted by the feature point extractingunit 154 b, an average color bar generating unit 154 d that generates anaverage color bar 60 by using the selected image data, and a screengenerating unit (screen generating means) 154 e that generates a GUIscreen by using the selected image data and the average color bar 60.

The rotation correcting unit 154 a is rotation-correcting means thatrotation-corrects corresponding image data on the basis of theorientation of the capsule medical device 10 specified by the CPU 133 asthe rotation specifying means, and rotation-corrects image data so thatthe tilts (hereinbelow, simply called rotation amounts) on the displayplane of the reference direction Ds of each image with respect to theupward direction Du (refer to FIG. 8) of the screen coincide among aplurality of images.

In the first embodiment, each of image data pieces is rotation-correctedso that the reference direction Ds and the upward direction Du of thescreen coincide with each other in all of images. A correction amount(that is, a rotation amount) at the time of the rotation correction canbe specified from the tilt on the display plane of the specifieddirection Ui of each image with respect to the reference direction Ds.Specifically, by specifying how much the specified direction Ui turnswith respect to the reference direction Ds in a plane parallel to thelight reception face of the CCD array 11 a, the rotation amount(correction amount) used for the rotation correction can be specified.In other words, by projecting the reference direction Ds to the lightreception face and obtaining the angle of the specified direction Uiwith respect to the reference direction Ds after projection, therotation amount A used for the rotation correction can be specified. Therotation correcting unit 154 a rotation-corrects image data inaccordance with the specified rotation amount, thereby making thereference direction Ds in the image data coincide with the upwarddirection Us of the screen. As a result, the orientation of a region inan image captured as a subject can be made coincide in a plurality ofimages. The image data subjected to the rotation correction may be heldin, for example, the memory 134 or the like regardless of whether it isselected.

The feature point extracting unit 154 b extracts a feature point of eachimage data subjected to the rotation correction (that is, on the frameunit basis) and supplies it as an extraction result to the imageselecting unit 154 c.

To the image selecting unit 154 c, the image data subjected to therotation correction is also entered. The image selecting unit 154 cselects image data in which a scene change occurs or image dataincluding a peculiar shape on the basis of the feature point extractionresult entered from the feature point extracting unit 154 b, andsupplies it to the average color bar generating unit 154 d and thescreen generating unit 154 e.

The average color bar generating unit 154 d functions as average colorgenerating means generating the average color bar 60 by calculating anaverage color of the image data subjected to the rotation correction andconnecting generated images of average colors in accordance with theorder of the image data. In the embodiment, the average color bargenerating unit 154 d generates an average color bar by using image dataselected by the image selecting unit 154 c. The details of the operationof the average color bar generating unit 154 d and the average color bar60 generated by the average color bar generating unit 154 d will bedescribed later.

The screen generating unit 154 e generates, for example, a GUI screen asillustrated in FIG. 8. As shown in FIG. 8, in the GUI screen generatedby the image processing unit 154, patient information g11, diagnosisinformation g12, a main image display region g13, a sub image displayregion g14, reproduction control buttons g15, and the average color bar60 are incorporated. The observer switches an image displayed in themain image display region g13 by selecting the reproduction controlbuttons g15 by operating the input unit 156 such as the mouse. Forexample, in the case where the observer selects an image reproductionstop button (the “∥” button in the reproduction control buttons g15),using the image being displayed in the main image display region g13 asa center, reduction images preceding and subsequent to the image beingdisplayed are displayed. The arrow Du direction in the main imagedisplay region g13 is the upward direction Du of the screen.

Further, in the sub image display region g14, a scroll bar g14 s and aslider g14 a are disposed adjacent to each other. The scroll bar g14 sis linked to the time base of capturing timings of images successivelyobtained. Therefore, the observer can slide a reduction image displayedin the sub image display region g14 by moving the slider g14 a along thescroll bar g14 s.

The average color bar 60 is a GUI generated by generating imagesschematically expressing colors as characteristics of the images for allof image data and arranging the images along the time base “t” (refer toFIG. 10 or 15). The arrangement of images along the time basecorresponds to, as a result, arrangement of images along the movementlocus in the lumen 902 of the capsule medical device 10. The color as afeature of each image (average color) can be obtained by, for example,dividing a target image into a plurality of pieces (for example, fourpieces) in the vertical direction and averaging colors at feature pointsin the divided regions. Therefore, the observer can visually recognizethe place in the lumen 902, in which a region to be noted exists byreading the average color bar 60.

In the average color bar 60, the slider g16 a indicating image data in aposition on the time bar, which is presently displayed is currentlyexpressed in the main image display region g13. The observer can switchimage data to be displayed in the main image display region g13 to imagedata in a target position on the time base by moving the slider g16 a byusing the mouse or the like in the input unit 156.

Operation

As described above, the subject 900 of the capsule medical device 10 mayhave any posture. Therefore, the capsule medical device 10 passivelymoves in the lumen of the subject 900 while rotating in variousdirections by its peristaltic movement. In an example shown in (a) to(c) in FIG. 9, when it is assumed that the reference direction Ds inimage data Im11 captured at a first imaging timing and the specifieddirection Ui are the same, the specified direction Ui in image data Im12captured at a second imaging timing as the immediately successive timinghas a tilt of 90° from the reference direction Ds and, further, thespecified direction Ui has a tilt of 180° from the reference directionDs at a third imaging timing in image data Im13 captured at theimmediately successive timing. That is, from (a) to (c) in FIG. 9, thecapsule medical device 10 turns by 90° each around the symmetrical axisin the longitudinal direction. Therefore, as shown in (d) to (f) in FIG.9, the specified direction Ui in the image data Im11 to Im13 captured bythe capsule medical device 10 turns by 90° each with respect to thereference direction Ds. As a result, as shown in (d) to (f) in FIG. 9,the reference direction Ds of the image data Im11 to Im13 displayed inthe screen turns by 90° each with respect to the upward direction Du ofthe screen. When the reference direction Ds of image data arbitrarilyturns with respect to the upward direction Du of the screen, there is acase such that a part p1 as a feature included in a division region A3in division regions A1 to A4 in the image data Im11 captured at thefirst imaging timing lies in two regions of the division regions A1 andA2 in the image data Im12 captured at the second imaging timing, and isincluded in the division region A2 in the image data Im13 captured atthe third imaging timing. FIG. 9 is a diagram showing the image dataIm11 to Im13 which is successive in time obtained when the capsulemedical device 10 images the same part p1 in the subject 900.

As shown in FIG. 9, when the specified direction Ui of image dataobtained by imaging the same part p1 varies with respect to thereference direction Ds, cases occur such that the position of the partp1 indicated in the average color bar 60 generated by using the imagedata Im11 to Im13 varies without being arranged in the horizontaldirection as shown in FIG. 10 (refer to regions P1 to P3 in FIG. 10) orthe density of color decreases since the part lies in different divisionregions (refer to the regions P2 a and P2 b in FIG. 10). FIG. 10 is adiagram showing an example of the average color bar 60 generatedaccording to the first embodiment. In FIG. 10, the regions P1, P2 a andP2 b, and P3 denote images obtained by averaging the feature colors inthe division regions (A3, A1 and A2, and A2) each including the samepart p1, respectively.

The operation of the medical system 1 according to the first embodimentcapable of preventing occurrence of cases as described above will now bedescribed in detail with reference to the drawings. In the firstembodiment, as described above, image data is two-dimensionallyrotation-corrected on the display face so that the reference directionDs of each of images coincides with the upward direction Du of thescreen.

FIG. 11 is a flowchart showing an example of schematic operation of thecapsule medical device 10 according to the first embodiment. FIG. 12 isa flowchart showing an example of schematic operation of the receivingdevice 130 according to the first embodiment. FIG. 13 is a flowchartshowing an example of schematic operation of the display device 150according to the first embodiment.

As shown in FIG. 11, after startup, the capsule medical device 10executes imaging operation periodically (for example, at time T (=0.5second) intervals), thereby obtaining image data (steps S101 and S102).Subsequently, the capsule medical device 10 obtains time at which theimage data is obtained (step S103) and adds the time as a time stamp tothe image data (step S104). The capsule medical device 10 transmits, asa wireless signal, the image data to which the time stamp is added (stepS105), and returns to the step S101. By such operation, image data isperiodically transmitted by radio from the capsule medical device 10 tothe receiving device 130. The operation of the capsule medical device 10shown in FIG. 11 is continued until no power remains in the battery 16in the capsule medical device 10.

On the other hand, as shown in FIG. 12, the receiving device 130, forexample, always monitors whether image data is received from the capsulemedical device 10 (No in step S111). In the case where image data isreceived (Yes in step S111), the receiving device 130 estimates spatialspread of an electromagnetic wave (electric field distribution) from thephase of the electromagnetic wave (sign for orientation detection) ineach of the antennas 120 detected by the transmitting/receiving circuit131 at the time of reception of the image data in step S111 and thestrength in each of the antennas 120 detected by the RSSI circuit 131 a,specifies the orientation with respect to the reference direction Ds ofthe capsule medical device 10 (that is, the orientation with respect tothe reference direction Ds, of the specified direction Ui) in the CPU133, and generates it as orientation data (step S112).

Next, the receiving device 130 adds the orientation data generated inthe CPU 133 to the image data received in step S111 (step S113) and, asa result, either stores the image data to which the orientation data andthe time stamp are added from the interface 137 into the portablerecording medium 140 or transmits the image data from the interface 137to the display device 150 via the communication cable 159 (step S114).After that, the receiving device 130 determines whether the operation iscontinued, for example, whether an operation end instruction is receivedfrom the operation unit 135 (step S115). In the case of continuing theoperation (Yes in step S115), the receiving device 130 returns to stepS111 and waits for reception of next image data. On the other hand, inthe case where the operation is not continued (No in step S115), theoperation is finished.

As shown in FIG. 13, when the display device 150 receives one or morepieces of image data from the receiving device 130 via the portablerecording medium 140 or the communication cable 159 (step S121), thedisplay device 150 inputs the image data to the image processing unit154. The image processing unit 154 sequentially selects the input imagedata one by one (step S122) and inputs the image data or the orientationdata added to the image data to the rotation correcting unit 154 a. Therotation correcting unit 154 a two-dimensionally rotation-corrects theimage data on the display face by using the orientation data added tothe input image data, thereby making the reference direction Ds of theimage data coincide with the upward direction Du of the screen (stepS123). The operations in step S122 and S123 are repeated (No in stepS124) until the rotation correction is performed on all of the imagedata which is input in step S121 (Yes in step S124). The image datasubjected to the rotation correction is sequentially supplied from therotation correcting unit 154 a to the feature point extracting unit 154b and the image selecting unit 154 c.

The feature point extracting unit 154 b to which the image datasubjected to the rotation correction is supplied extracts a featurepoint included in the image data (step S125). The extracted featurepoint is supplied to the image selecting unit 154 c.

The image selecting unit 154 c selects image data satisfying apredetermined condition from a plurality of pieces of image data on thebasis of the image data subjected to the rotation correction suppliedfrom the rotation correcting unit 154 a as a result of step S124 and thefeature point extraction result supplied from the feature pointextracting unit 154 b as a result of step S125 (step S126). For example,the image selecting unit 154 c selects image data having a feature pointlargely different from a feature point of image data of last time. Theselected image data is input to each of the average color bar generatingunit 154 d and the screen generating unit 154 e. A threshold is, forexample, a value for selecting image data in which a scene change occursand image data including a peculiar shape. The threshold can be derivedin advance by experience, experiment, simulation, or the like.

The average color bar generating unit 154 d generates an image of theaverage color bar 60 by which a schematic image of each image can beseen at a glance along time series from all of the selected image datasubjected to the rotation correction (average color bar generatingprocess: step S127). An example of the rotation correction in step S123and an example of the average color bar 60 generated in step S127 willbe described specifically later by using FIGS. 14 and 15. The generatedimage of the average color bar 60 is input to the screen generating unit154 e.

The screen generating unit 154 e to which the image of the average colorbar 60 and the selected image data is input executes a screen generatingprocess of generating a GUI screen as shown in FIG. 8 by using the imageof the average color bar 60 and the selected image data (step S128) and,after that, finishes the process. The generated GUI screen is input tothe display unit 155 via the control unit 151 and displayed to theobserver. As a result, the GUI function using the GUI screen and theinput unit 156 is provided to the observer.

Using FIGS. 14 and 15, an example of the rotation correction in stepS123 and an example of the average color bar 60 generated in step S127will be described. FIG. 14 is a diagram for explaining the rotationcorrection of image data in step S123 in FIG. 13. FIG. 15 is a diagramshowing an example of the average color bar 60 generated by using theimage data subjected to the rotation correction in step S127 in FIG. 13.Image data Im11 to Im13 shown in (a) to (c) in FIG. 14 corresponds tothe image data Im11 to Im13 shown in FIG. 9.

As shown in (a) in FIG. 14, in the image data Im11 obtained at the firstimaging timing, the specified direction Ui and the reference directionDs coincide with each other. Consequently, the rotation amount(correction amount) A at the time of the rotation correction on theimage data Im11 is 0°. As shown in (b) in FIG. 14, in the image dataIm12 obtained at the second imaging timing, the angle of the specifieddirection Ui with respect to the reference direction Ds is 90°.Therefore, the rotation amount (correction amount) A at the time of therotation correction on the image data Im12 is 90°. Further, as shown in(c) in FIG. 14, in the image data Im13 obtained at the third imagingtiming, the angle of the specified direction Ui with respect to thereference direction Ds is 180°. Therefore, the rotation amount(correction amount) A at the time of the rotation correction on theimage data Im13 is 180°. In the rotation correcting unit 154 a and stepS123, by performing the rotation correction on the image data by usingthe rotation amount (correction amount) A obtained as described above,as shown in (d) to (f) in FIG. 14, the reference direction Ds of each ofimage data Im21 to Im23 is made coincide with the upward direction Du ofthe screen.

As a result of the rotation correction as described above, asillustrated in (d) to (f) in FIG. 14, the same part p1 in image dataIm21 to Im23 is included in the same division region A3. Consequently,as shown in FIG. 15, the positions of regions P21 to P23 including thesame part p1 in the average color bar 60 generated by using the imagedata Im21 to Im23 subjected to the rotation correction can be aligned inthe horizontal direction in the division region A3. (d) in FIG. 14 showsthe image data Im21 obtained by rotation-correcting the image data Im11of (a) in FIG. 14, (e) in FIG. 14 shows the image data Im22 obtained byrotation-correcting the image data Im12 of (b) in FIG. 14, and (f) inFIG. 14 shows the image data Im23 obtained by rotation-correcting theimage data Im13 of (c) in FIG. 14.

In the first embodiment as described above, the orientations of aplurality of pieces of image data can be aligned by performing therotation correction on image data on the basis of the orientation withrespect to the reference direction Ds of the capsule medical device 10at the time of imaging, so that the medical system 1 and the imageprocessing method enabling reduced time and effort on diagnosis andimproved accuracy of a diagnosis result can be realized.

Although the rotation correction on image data (refer to step S123 inFIG. 13) is executed in the display device 150 in the first embodiment,the invention is not limited to the case but can be variously modifiedby, for example, executing the rotation correction in the receivingdevice 130 or the like.

Modification 1-1

In the medical system 1 according to the first embodiment, the caseusing the electromagnetic wave generating source (antenna 15 a) as thesignal source has been described as an example. However, the inventionis not limited to the case. A magnetic field generation source can beused as the signal source. In the following, this case will be describedin detail as modification 1-1 of the first embodiment with reference tothe drawings. In the following description, the same reference numeralsare designated to components similar to those of the foregoingembodiment for simplification of explanation, and their description willnot be repeated.

FIG. 16 is a schematic diagram showing a schematic configuration of amedical system 1A according to the modification 1-1. FIG. 17 is a blockdiagram showing a schematic configuration example of a capsule medicaldevice 10A and a receiving device 130A according to the modification1-1.

As shown in FIG. 16, in the medical system 1A, in comparison with themedical system 1 shown in FIG. 1, the capsule medical device 10 isreplaced with the capsule medical device 10A, and the receiving device130 is replaced with the receiving device 130A. Further, in the medicalsystem 1A, the receiving device 130 has magnetic sensors 123 a and 123 bconnected to the receiving device 130A via a cable 124.

The capsule medical device 10A has, as shown in FIG. 17, a permanentmagnet 17 a in addition to a configuration similar to that of thecapsule medical device 10 shown in FIG. 5.

The permanent magnet 17 a is magnetic field forming means for forming amagnetic field which reaches the outside of the subject 900 andfunctions as a signal source generating a sign for orientation detection(the magnetic field in the example) for specifying the orientation ofthe capsule medical device 10A (that is, tilt of the specified directionUi) with respect to the reference direction Ds. The permanent magnet 17a is fixed to the casing 18. The invention is not limited to thepermanent magnet 17 a but can be applied to anything as long as it canform a magnetic field reaching the outside of the subject 900, such as acoil.

Preferably, the permanent magnet 17 a is fixed in the casing 18 so thatthe direction of the magnetic pole of the permanent magnet 17 acoincides with the orientation of the specified direction Ui. With theconfiguration, the orientation with respect to the reference directionDs of the permanent magnet 17 a can be directly used as the orientationwith respect to the reference direction Ds of the specified directionUi, so that the process in the receiving device 130A which will bedescribed later can be lessened.

On the other hand, as shown in FIG. 17, the receiving device 130A has,in addition to a configuration similar to the configuration of thereceiving device 130 shown in FIG. 5, the plurality of magnetic sensors123 a and 123 b fixed to the surface (for example, the jacket 122 or thelike) of the subject 900 and a signal detecting circuit 131A executing apredetermined signal process on a detection signal read from themagnetic sensors 123 a and 123 b.

Each of the magnetic sensors 123 a and 123 b is, for example, a triaxialmagnetic sensor in which three coils whose center axes correspond to thex axis, y axis, and z axis are combined, and functions as an observationpoint as magnetic field detecting means for observing a sign fororientation detection (a magnetic field in the embodiment) generatedfrom the permanent magnet 17 a as a signal source. The invention,however, is not limited to the sensor but a triaxial magnetic sensormade by, for example, a magnetoresistive element, a magnetic impedanceelement (MI element), a hall element, or the like can be also employed.

The number of the magnetic sensors 123 a and 123 b, an arrangementpattern, and an object to which the magnetic sensors 123 a and 123 b canbe variously modified as long as the number and the arrangement patternby which a CPU 133A can estimate/specify the spatial spread (magneticfield distribution) of the magnetic field formed by the permanent magnet17 a of the capsule medical device 10A introduced in the subject 900 andthe fixation object which can be substantially fixed to the subject 900are used. In the description, the number of the magnetic sensors 123 aand 123 b is at least two.

A potential change detected by the magnetic sensors 123 a and 123 b isread as a detection signal by the signal detection circuit 131A of thereceiving device 130A via the cable 124. The signal detection circuit131A performs a process such as fast Fourier transformation (FFT) on theread signal and supplies the processed signal to the CPU 133A.

Like the CPU 133 in the foregoing first embodiment, the CPU 133Afunctions as orientation specifying means specifying the orientation ofthe capsule medical device 10A (that is, tilt of the specified directionUi) with respect to the reference direction Ds from the strength andorientation of the sign (magnetic field) for orientation detectionobserved at the observation points (the magnetic sensors 123 a and 123b). That is, the CPU 133A estimates the spatial spread of the magneticfield (magnetic field distribution) on the basis of the magnetic fieldstrength of a detection signal, the orientation of a line of magneticforce, and the like in each of the magnetic sensors 123 a and 123 bsupplied from the signal detection circuit 131A and specifies theorientation with respect to the reference direction Ds of the capsulemedical device 10A (that is, the orientation with respect to thereference direction Ds of the specified direction Ui). In a mannersimilar to the foregoing embodiment, information of the orientation(orientation data) with respect to the reference direction Ds of thespecified direction Ui specified by the CPU 133A is temporarily storedin association with image data received simultaneously or around thesame time from the capsule medical device 10A into the memory 134. Thestrength and orientation of the magnetic field formed by the permanentmagnet 17 a can be detected by, for example, a change in the magneticfield distribution when the capsule medical device 10A (that is, thepermanent magnet 17 a) moves.

As described above, in the modification 1-1, using the permanent magnet17 a as the signal source and using the plurality of magnetic sensors123 a and 123 b at observation points, the orientation data indicativeof the orientation with respect to the reference direction Ds of thespecified direction Ui is generated. The other configuration is similarto that of any of the foregoing embodiments (including theirmodifications).

Next, the operation of the medical system 1A according to themodification 1-1 will be described in detail with reference to thedrawings. Since the operation of the capsule medical device 10A and thedisplay device 150 in the modification 1-1 is similar to that of thefirst embodiment, in the description, the operation of the receivingdevice 130A will be described below. FIG. 18 is a flowchart showing anexample of outline operation of the receiving device 130A according tothe modification 1-1.

As shown in FIG. 18, the receiving device 130A, for example, alwaysmonitors whether image data is received from the capsule medical device10A (No in step S111-1). In the case where image data is received (Yesin step S111-1), the receiving device 130A reads detection signals fromthe magnetic sensors 123 a and 123 b by using the signal detectioncircuit 131A, executes a predetermined signal process (step S112-1),subsequently, estimates spatial spread of a magnetic field (magneticfield distribution) from the magnetic field strength of the detectionsignal subjected to the signal process, the orientation of the line ofmagnetic force, and the like, specifies the orientation with respect tothe reference direction Ds of the capsule medical device 10A (that is,orientation with respect to the reference direction Ds of the specifieddirection Ui), and generates it as orientation data (step S113-1).

Next, like the operation described with reference to FIG. 12 in thefirst embodiment, the receiving device 130A adds the orientation datagenerated in the CPU 133A to the image data received in step S111-1(step S114-1) and, as a result, either stores the image data to whichthe orientation data and the time stamp are added from the interface 137into the portable recording medium 140 or transmits the image data fromthe interface 137 to the display device 150 via the communication cable159 (step S115-1). After that, the receiving device 130A determineswhether the operation is continued, for example, whether an operationend instruction is received from the operation unit 135 (step S116-1).In the case of continuing the operation (Yes in step S116-1), thereceiving device 130A returns to step S111-1 and waits for reception ofnext image data. On the other hand, in the case where the operation isnot continued (No in step S116-1), the operation is finished.

With the configuration and operation as described above, in themodification 1-1, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Ds of the capsulemedical device 10A at the time of imaging, so that the medical system10A and the image processing method enabling reduced time and effort ondiagnosis and improved accuracy of a diagnosis result can be realized.

Although the case of using the permanent magnet 17 a as a signal sourcehas been described as an example in the modification 1-1, the inventionis not limited to the case but can use as a signal source, for example,as shown in a capsule medical device 10A′ of FIG. 19, an LC resonancecircuit 17 b (magnetic field forming means) generating an inducedmagnetic field at a predetermined resonance frequency spontaneously orwhen induced. FIG. 19 is a block diagram showing a schematicconfiguration example of the capsule medical device 10A′ and thereceiving device 130A according to another example of the modification1-1.

For example, in the case of generating the induced magnetic fieldspontaneously (this will be called an active method), a current signalof an almost resonance frequency is supplied from, for example, theprocessing unit 12 (signal generating means) to the LC resonance circuit17 b. On the other hand, for example, in the case of generating aninduced magnetic field by being induced by an external magnetic field(this will be called a passive method), a magnetic field (drive magneticfield) of a frequency almost equal to the resonance frequency of the LCresonance circuit 17 b is generated in a detection space in which thecapsule medical device 10A′ is introduced. The CPU 133A specifies theorientation with respect to the reference direction Ds of the capsulemedical device 10A′ on the basis of the orientation and strength of themagnetic field indicated by a detection signal read from each of themagnetic sensors 123 a and 123 b (that is, the orientation and strengthof the magnetic field in the position of each of the magnetic sensors123 a and 123 b) and generates orientation data from the specifiedorientation.

Modification 1-2

As the signal source in the first embodiment, an ultrasound generationsource can be used. In the following, this case will be described indetail as modification 1-2 of the first embodiment with reference to thedrawings. In the following description, the same reference numerals aredesignated to components similar to those of the foregoing embodiment orits modification for simplification of explanation, and theirdescription will not be repeated.

FIG. 20 is a schematic diagram showing a schematic configuration of amedical system 1B according to the modification 1-2. FIG. 21 is a blockdiagram showing a schematic configuration example of a capsule medicaldevice 10B and a receiving device 130B according to the modification1-2.

As shown in FIG. 20, in the medical system 1B, in comparison with themedical system 1 shown in FIG. 1, the capsule medical device 10 isreplaced with the capsule medical device 10B, and the receiving device130 is replaced with the receiving device 130B. Further, in the medicalsystem 1B, the receiving device 130B is provided with acoustic sensors125 a and 125 b connected to the receiving device 130B via a cable 126.

The capsule medical device 10B has, as shown in FIG. 21, at least twopiezoelectric elements 17 c and 17 d in addition to a configurationsimilar to that of the capsule medical device 10 shown in FIG. 5.

The piezoelectric elements 17 c and 17 d are ultrasound generating meansfor generating an ultrasound wave which propagates the inside of thesubject 900 and reaches the outside surface, and functions as a signalsource generating a sign for orientation detection (the ultrasound wavein the example) for specifying the orientation of the capsule medicaldevice 10B (that is, tilt of the specified direction Ui) with respect tothe reference direction Ds.

Each of the piezoelectric elements 17 c and 17 d is fixed to the casing18 so that a part of it is exposed to the outside of the casing 18 whilemaintaining water-tightness of the casing 18. The invention is notlimited to the piezoelectric elements 17 c and 17 d but can be appliedto anything as long as it can serve as an ultrasound source.

Preferably, the piezoelectric elements 17 c and 17 d are arranged in astate where they are fixed in the casing 18 so as to coincide with theorientation of the specified direction Ui. With the configuration, theorientation with respect to the reference direction Ds of thearrangement direction of the piezoelectric elements 17 c and 17 d can bedirectly used as the orientation with respect to the reference directionDs of the specified direction Ui, so that the process in the receivingdevice 130B which will be described later can be lessened.

On the other hand, as shown in FIG. 21, the receiving device 130B has,in addition to a configuration similar to the configuration of thereceiving device 130 shown in FIG. 5, the plurality of acoustic sensors125 a and 125 b fixed to the surface (for example, the jacket 122 or thelike) of the subject 900 and a signal detecting circuit 131B executing apredetermined signal process on a detection signal read from theacoustic sensors 125 a and 125 b.

Each of the acoustic sensors 125 a and 125 b is constructed by using,for example, a microphone and functions as an observation point asultrasound detecting means for observing a sign for orientationdetection (an ultrasound wave in the embodiment) generated from theplurality of piezoelectric elements 17 c and 17 d as a signal source.The invention, however, is not limited to the sensors but, for example,a piezoelectric element or the like may be used.

The number of the acoustic sensors 125 a and 125 b, an arrangementpattern, and an object to which the acoustic sensors 125 a and 125 b arefixed can be variously modified as long as the number and thearrangement pattern by which a CPU 133B can estimate/specify theorientation of the capsule medical device 10B from the strength andphase at the plurality of observation points of ultrasound waves (theacoustic sensors 125 a and 125 b) generated by the piezoelectricelements 17 c and 17 d of the capsule medical device 10B introduced inthe subject 900 and the fixation object which can be substantially fixedto the subject 900 are used. In the description, the number of theacoustic sensors 125 a and 125 b is at least two.

A potential change which occurs in the acoustic sensors 125 a and 125 bis read as a detection signal by the signal detection circuit 131B ofthe receiving device 130B via the cable 126. The signal detectioncircuit 131B performs a process such as fast Fourier transformation(FFT) on the read signal and supplies the processed signal to the CPU133B.

Like the CPU 133 in the foregoing first embodiment, the CPU 133Bfunctions as orientation specifying means specifying the orientation ofthe capsule medical device 10B (that is, tilt of the specified directionUi) with respect to the reference direction Ds from the strength andphase of the sign (ultrasound wave) for orientation detection observedat the observation points (the acoustic sensors 125 a and 125 b). Thatis, the CPU 133B estimates the spatial spread of the ultrasound wave(ultrasound distribution) on the basis of the phase, strength, and thelike of a detection signal in each of the acoustic sensors 125 a and 125b supplied from the signal detection circuit 131B and specifies theorientation with respect to the reference direction Ds of the capsulemedical device 10B (that is, the orientation with respect to thereference direction Ds of the specified direction Ui). In a mannersimilar to the foregoing embodiment, information of the orientation(orientation data) with respect to the reference direction Ds of thespecified direction Ui specified by the CPU 133B is temporarily storedin association with image data received simultaneously or around thesame time from the capsule medical device 10B into the memory 134.

As described above, in the modification 1-2, using the plurality ofpiezoelectric elements 17 c and 17 d as the signal source and using theplurality of acoustic sensors 125 a and 125 b at observation points, theorientation data indicative of the orientation with respect to thereference direction Ds of the specified direction Ui is generated. Theother configuration is similar to that of any of the foregoingembodiments (including their modifications).

Next, the operation of the medical system 1B according to themodification 1-2 will be described in detail with reference to thedrawings. Since the operation of the display device 150 in themodification 1-2 is similar to that of the first embodiment, in thedescription, the operation of the capsule medical device 10B and thereceiving device 130B will be described below. FIG. 22 is a flowchartshowing an example of outline operation of the capsule medical device10B according to the modification 1-2. FIG. 23 is a flowchart showing anexample of outline operation of the receiving device 130B according tothe modification 1-2.

As shown in FIG. 22, after startup, the capsule medical device 10Bexecutes imaging operation periodically (for example, at intervals oftime T (=0.5 second)), thereby obtaining image data (steps S101-2 toS102-2). The capsule medical device 10B generates a voltage signal of apredetermined frequency in the processing unit 12 and supplies it to thepiezoelectric elements 17 c and 17 d, thereby generating ultrasonicwaves from the piezoelectric elements 17 c and 17 d (step S103-2).Subsequently, the capsule medical device 10B obtains time at which theimage data is obtained (step S104-2) and adds the time as a time stampto the image data (step S105-2). The capsule medical device 10Btransmits the image data to which the time stamp is added as a wirelesssignal (step S106-2) and returns to the step S101-2. By such operation,the image data is periodically transmitted by radio from the capsulemedical device 10B to the receiving device 130B, and an ultrasonic wavefor making the receiving device 130B specify the orientation of thecapsule medical device 10B is generated. The operation of the capsulemedical device 10B shown in FIG. 22 is continues until no power remainsin the battery 16 in the capsule medical device 10B.

On the other hand, as shown in FIG. 23, the receiving device 130B, forexample, always monitors whether image data is received from the capsulemedical device 10B (No in step S111-2). In the case where image data isreceived (Yes in step S111-2), the receiving device 130B reads detectionsignals from the acoustic sensors 125 a and 125 b by using the signaldetection circuit 131B, executes a predetermined signal process (stepS112-2), subsequently, estimates spatial positions of the piezoelectricelements 17 c and 17 d as an ultrasound source from the phase, strength,and the like of the detection signals subjected to the signal process,specifies the orientation with respect to the reference direction Ds ofthe capsule medical device 10B (that is, orientation with respect to thereference direction Ds of the specified direction Ui) in the CPU 133B,and generates it as orientation data (step S113-2).

Next, like the operation described with reference to FIG. 12 in thefirst embodiment, the receiving device 130B adds the orientation datagenerated in the CPU 133B to the image data received in step S111-2(step S114-2) and, as a result, either stores the image data to whichthe orientation data and the time stamp are added from the interface 137into the portable recording medium 140 or transmits the image data fromthe interface 137 to the display device 150 via the communication cable159 (step S115-2). After that, the receiving device 130B determineswhether the operation is continued, for example, whether an operationend instruction is received from the operation unit 135 (step S116-2).In the case of continuing the operation (Yes in step S116-2), thereceiving device 130B returns to step S111-2 and waits for reception ofnext image data. On the other hand, in the case where the operation isnot continued (No in step S116-2), the operation is finished.

With the configuration and operation as described above, in themodification 1-2, in a manner similar to the first embodiment (and itsmodification), the orientations of a plurality of pieces of image datacan be aligned by performing the rotation correction on image data onthe basis of the orientation with respect to the reference direction Dsof the capsule medical device 10B at the time of imaging, so that themedical system 1B and the image processing method enabling reduced timeand effort on diagnosis and improved accuracy of a diagnosis result canbe realized.

Second Embodiment

Although the case of disposing the signal source (antenna 15 a) in thecapsule medical device 10 and fixing the observation points (antennas120) on the outer surface of the subject 900 has been described as anexample in the first embodiment, the invention is not limited to thecase. The signal source can be fixed to the outer face of the subject900 and the observation points can be disposed in the capsule medicaldevice. In the following, the case will be described in detail as asecond embodiment with reference to the drawings. In the followingdescription, the same reference numerals are designated to componentssimilar to those of the forgoing embodiment and its modifications forsimplicity of explanation, and their detailed description will not berepeated.

FIG. 24 is a schematic diagram showing a schematic configuration of amedical system 2 according to the second embodiment. FIG. 25 is a blockdiagram showing an example of a schematic configuration of a capsulemedical device 20 and a receiving device 230 according to the secondembodiment.

As illustrated in FIG. 24, in the medical system 2, in comparison withthe medical system 1 shown in FIG. 1, the capsule medical device 10 isreplaced with the capsule medical device 20, and the receiving device130 is replaced with the receiving device 230. Further, in the medicalsystem 2, the antenna 120 (refer to FIG. 1) fixed to the surface of asubject 200 and the cable 121 are replaced with an antenna 220 and acable 221, respectively.

As shown in FIG. 25, the capsule medical device 20 has, in addition to aconfiguration similar to that of the capsule medical device 10 shown inFIG. 5, antennas 22 a and 22 b and a signal detection unit 21 fordetecting the phase and strength of the electromagnetic wave in theantennas 22 a and 22 b.

The antennas 22 a and 22 b are, for example, dipole antennas or loopantennas and function as observation points for observing a sign(electromagnetic wave) for orientation detection emitted from theantenna 220 as a signal source which will be described later.Preferably, the antennas 22 a and 22 b are disposed so as to be apartfrom each other as much as possible in the casing 18.

Preferably, the antennas 22 a and 22 b are arranged in a state wherethey are fixed in the casing 18 so as to coincide with the orientationof the specified direction Ui. With the arrangement, the orientationwith respect to the reference direction Ds of the arrangement directionof the antennas 22 a and 22 b can be directly used as the orientationwith respect to the reference direction Ds of the specified directionUi, so that the process in the receiving device 230 which will bedescribed later can be lessened. Further, the signal detection unit 21includes, for example, an RSSI circuit (not shown) for detectingstrength of the electromagnetic wave received in each of the antennas 22a and 22 b.

The signal detection unit 21 executes, on a detection signal suppliedfrom each of the antennas 22 a and 22 b, frequency separation and apredetermined process including a process of detecting the phase of anelectromagnetic wave (a sign for orientation detection) between theantennas 22 a and 22 b and strength in each of the antennas 22 a and 22b. The signal detection unit 21 adds, as signal detection data, thedetected phase and strength in each of the antennas 22 a and 22 b toimage data obtained at the same time or around the same time.

The signal detection data includes data corresponding to the phase ofthe electromagnetic wave (sign for orientation detection) between theantennas 120 detected by the transmitting/receiving circuit 131 in thereceiving device 130 in the first embodiment and the strength of theelectromagnetic wave (sign for orientation detection) observed at eachantenna 120 detected by the RSSI circuit 131 a of thetransmitting/receiving circuit 131. To the image data, a time stamp isalso added in a manner similar to the first embodiment. The image datato which the signal detection data and the time stamp are added istransmitted by radio from the antenna 15 a to the receiving device 230from the processing unit 12 via the transmitting/receiving unit 14.

On the other hand, in the receiving device 230, as shown in FIG. 25, ina configuration similar to the receiving device 130 shown in FIG. 5, theantenna 120 is replaced with the antenna 220, and thetransmitting/receiving circuit 131 is replaced with atransmitting/receiving circuit 231.

Like the antenna 15 a of the first embodiment, the antenna 220 is, forexample, an antenna having directivity and functions as a signal sourcegenerating a sign for orientation detection (electric field in theexample) for specifying the orientation of the capsule medical device 20with respect to the reference direction Ds (that is, tilt of thespecified direction Ui). In the second embodiment, a loop antenna isused as the antenna 220. However, the invention is not limited to theloop antenna. Any antenna is applicable as long as it can detect theorientation of the capsule medical device 20 with respect to thereference direction Ds on the basis of the phase and strength of theelectromagnetic wave (sign for orientation detection) at the antennas 22a and 22 b.

The antenna 220 having the directivity is fixed on the surface (forexample, the jacket 122 or the like) of the subject 900. The antenna 220is fixed to the outside surface of the subject 900 so that the centerline of the loop of the antenna 220 (corresponding to the symmetricalaxis of an electric field distribution shape of the electromagnetic wavegenerated by the antenna 15 a) and the reference direction Ds becomeparallel to each other. Consequently, even in the case where the capsulemedical device 20 rotates using the center line in the longitudinaldirection as an axis, the orientation of the specified direction Ui ofthe capsule medical device 20 with respect to the reference direction Dscan be specified on the basis of the phase and strength of theelectromagnetic wave received by the antennas 22 a and 22 b of thecapsule medical device 20.

Like the transmitting/receiving circuit 131, the transmitting/receivingcircuit 231 transmits/receives signals to/from the capsule medicaldevice 20 via the antenna 220. As described above, thetransmitting/receiving circuit 231 according to the second embodimentoutputs an electromagnetic wave as a sign for orientation detection tothe antenna 220 periodically (for example, twice or more per second).

The reception signal supplied from the antenna 220 to thetransmitting/receiving circuit 231 is supplied to the signal processingcircuit 132. In the second embodiment, as described above, the signaldetection data is added to the image data received from the capsulemedical device 20. The signal processing circuit 132 executes apredetermined process on the input signal (particularly, image data),specifies the signal detection data added to the image data, andsupplies it to the CPU 133.

The CPU 133 functions as orientation specifying means estimating spatialspread (electric field distribution) of the electromagnetic wave (signfor orientation detection) from the phase of the electromagnetic wave(sign for orientation detection) at the antennas 22 a and 22 b includedin the signal detection data and strength of the electromagnetic wave(sign for orientation detection) at the antennas 22 a and 22 b detectedby the RSSI circuit of the signal detection unit 21 and specifying theorientation with respect to the reference direction Ds of the capsulemedical device 20 (that is, orientation with respect to the referencedirection Ds of the specified direction Ui). Since the method ofestimating the electric field distribution is similar to that of thefirst embodiment, its detailed description will not be repeated.

As described above, in the second embodiment, the antenna 220 as asignal source is fixed to the outside surface of the subject 900, theantennas 22 a and 22 b as observation points are disposed in the capsulemedical device 20, and orientation data indicative of the orientationwith respect to the reference direction Ds of the specified direction Uiis generated on the basis of the electromagnetic wave from the antenna220 observed at the antennas 22 a and 22 b. The other configuration issimilar to any of those in the foregoing embodiments (including theirmodifications).

Next, the operation of the medical system 2 according to the secondembodiment will be described in detail with reference to the drawings.Since the operation of the display device 150 in the second embodimentis similar to that of the first embodiment, in the description, theoperation of the capsule medical device 20 and the receiving device 230will be described below. FIG. 26 is a flowchart showing an example(No. 1) of outline operation of the capsule medical device 20 accordingto the second embodiment. FIG. 27 is a flowchart showing an example (No.2) of outline operation of the capsule medical device 20 according tothe second embodiment. FIG. 28 is a flowchart showing an example ofoutline operation of the receiving device 230 according to the secondembodiment.

As shown in FIG. 26, after startup, the capsule medical device 20monitors the antennas 22 a and 22 b periodically (for example, atintervals of time T (0.5 second)), thereby receiving the electromagneticwave (sign for orientation detection) transmitted from the receivingdevice 230 periodically (for example, at intervals of time 0.5 second orless) (Yes in step S201). Subsequently, the capsule medical device 20obtains, as signal detection data, the strength and phase at each of theantennas 22 a and 22 b of the received electromagnetic wave (the signfor orientation detection) from the signal detection unit 21 (step S202)and temporarily stores the signal detection data in, for example, thememory unit 13, a not-shown cache memory or the like (step S203). Afterthat, the capsule medical device 20 returns to step S201 and waits forreception of the next electromagnetic wave (sign for orientationdetection) (No in step S201). The operation of the capsule medicaldevice 20 shown in FIG. 26 is continued until no power remains in thebattery 16 in the capsule medical device 20.

In parallel to the operations shown in FIG. 26, the capsule medicaldevice 20 executes operations shown in FIG. 27. As shown in FIG. 27,after startup, by executing the imaging operation periodically (forexample, at intervals of time T (=0.5 second)), the capsule medicaldevice 20 obtains image data (steps S211 and S212). Subsequently, thecapsule medical device 20 acquires time at which the image data isobtained (step S213). The capsule medical device 20 also obtains thesignal detection data temporarily stored in the memory unit 13, a cachememory, or the like (step S214). The capsule medical device 20 adds theacquisition time as a time stamp to the image data and adds the obtainedsignal detection data to the image data (step S215). The capsule medicaldevice 20 transmits the image data to which the time stamp and thesignal detection data is added as a wireless signal (step S216) andreturns to step S211. By such operation, the image data to which thetime stamp and the signal detection data is added is periodicallytransmitted by radio from the capsule medical device 20 to the receivingdevice 230. The operations of the capsule medical device 20 shown inFIG. 27 are continued until no power remains in the battery 16 in thecapsule medical device 20.

On the other hand, as shown in FIG. 28, for example, the receivingdevice 230 always or periodically outputs the electromagnetic wave (signfor orientation detection) from the antenna 220 (step S221) and monitorswhether image data is received from the capsule medical device 20 (No instep S222). In the case where image data is received (Yes in step S222),the receiving device 230 supplies the signal detection data included inthe image data received to the CPU 133, estimates spatial spread(electric field distribution) of an electromagnetic wave (sign fororientation detection) from the antenna 220, specifies the orientationwith respect to the reference direction Ds of the capsule medical device20 (that is, orientation with respect to the reference direction Ds ofthe specified direction Ui) in the CPU 133, and generates it asorientation data (step S223).

Next, like the operation described with reference to FIG. 12 in thefirst embodiment, the receiving device 230 adds the orientation datagenerated in the CPU 133 to the image data received in step S222 (stepS224) and, as a result, either stores the image data to which theorientation data and the time stamp are added from the interface 137into the portable recording medium 140 or transmits the image data fromthe interface 137 to the display device 150 via the communication cable159 (step S225). After that, the receiving device 230 determines whetherthe operation is continued, for example, whether an operation endinstruction is received from the operation unit 135 (step S226). In thecase of continuing the operation (Yes in step S226), the receivingdevice 230 returns to step S221 and repeats output of theelectromagnetic wave (sign for orientation detection) and waiting forreception of next image data. On the other hand, in the case where theoperation is not continued (No in step S226), the operation is finished.

With the configuration and operation as described above, in the secondembodiment, in a manner similar to the first embodiment (including itsmodifications), the orientations of a plurality of pieces of image datacan be aligned by performing the rotation correction on image data onthe basis of the orientation with respect to the reference direction Dsof the capsule medical device 20 at the time of imaging, so that themedical system 2 and the image processing method enabling reduced timeand effort on diagnosis and improved accuracy of a diagnosis result canbe realized.

Modification 2-1

Although the case of using the electromagnetic wave generation source(antenna 220) as a signal source in the medical system 2 of the secondembodiment has been described as an example, the invention is notlimited to the case but can use a magnetic field generation source as asignal source. In the following, the case will be described in detailwith reference to the drawings as modification 2-1 of the secondembodiment. In the following description, the same reference numeralsare designated to components similar to those of any of the foregoingembodiments and their modifications for simplicity of description andtheir description will not be repeated.

FIG. 29 is a schematic diagram showing a schematic configuration of amedical system 2A according to the modification 2-1. FIG. 30 is a blockdiagram showing a schematic configuration example of a capsule medicaldevice 20A and a receiving device 230A according to the modification2-1.

As shown in FIG. 29, in the medical system 2A, in comparison with themedical system 2 shown in FIG. 24, the capsule medical device 20 isreplaced with the capsule medical device 20A, and the receiving device230 is replaced with the receiving device 230A. Further, in the medicalsystem 2A, the receiving device 230A is provided with an LC resonancecircuit 222 connected to the receiving device 230A via a cable 223.

As shown in FIG. 30, in the capsule medical device 20A, in aconfiguration similar to the capsule medical device 20 shown in FIG. 25,the antennas 22 a and 22 b are replaced with magnetic sensors 23 a and23 b, and the signal detection unit 21 is replaced with a signaldetection unit 21A.

Like the magnetic sensors 123 a and 123 b in the modification 1-1, eachof the magnetic sensors 23 a and 23 b is, for example, a triaxialmagnetic sensor in which three coils whose center axes correspond to thex axis, y axis, and z axis are combined, and functions as an observationpoint as magnetic field detecting means for observing a sign fororientation detection (a magnetic field in the modification) generatedfrom the LC resonance circuit 222 as a signal source. The invention,however, is not limited to the sensor but a triaxial magnetic sensormade by, for example, a magnetoresistive element, a magnetic impedanceelement (MI element), a hall element, or the like can be also employed.

The number and the arrangement pattern of the magnetic sensors 23 a and23 b can be variously modified as long as the number and the arrangementpattern by which the CPU 133A can estimate/specify the spatial spread(magnetic field distribution) of the magnetic field formed by the LCresonance circuit 222 fixed to the outside surface of the subject 900are used. In the description, the number of the magnetic sensors 23 aand 23 b is at least two.

Preferably, the magnetic sensors 23 a and 23 b are fixed in the casing18 so that their arrangement direction coincides with the orientation ofthe specified direction Ui. With the configuration, the arrangementdirection with respect to the reference direction Ds of the magneticsensors 23 a and 23 b can be directly used as the orientation withrespect to the reference direction Ds of the capsule medical device 20A(that is, the specified direction Ui), so that the process in thereceiving device 230A which will be described later can be lessened.

The signal detection unit 21A executes a predetermined process includinga bandpass process and a process of detecting the orientation andstrength of the magnetic field (sign for orientation detection) at themagnetic sensors 23 a and 23 b on the detection signal input from eachof the magnetic sensors 23 a and 23 b. The signal detection unit 21Aadds, as signal detection data, the detected orientation, strength, andthe like to image data obtained at the same time or around the sametime.

The signal detection data includes data corresponding to the orientationand strength of the magnetic field (sign for orientation detection) atthe magnetic sensors 123 a and 123 b detected by the signal detectioncircuit 131A in the receiving device 130A in the modification 1-1. Tothe image data, a time stamp is also added in a manner similar to themodification 1-1. The image data to which the signal detection data andthe time stamp are added is transmitted by radio from the antenna 15 ato the receiving device 230A from the processing unit 12 via thetransmitting/receiving unit 14.

On the other hand, in the receiving device 230A, as shown in FIG. 30, ina configuration similar to the receiving device 230 shown in FIG. 25, asignal generation circuit 224A for supplying a signal of resonancefrequency to the LC resonance circuit 222 via the cable 223 is provided.In the receiving device 230A, in a configuration similar to thereceiving device 230 shown in FIG. 25, the antenna 220 and thetransmitting/receiving circuit 231 are replaced with the antenna 120 andthe transmitting/receiving circuit 131 in the first embodiment,respectively, and the CPU 133 is replaced with the CPU 133A in themodification 1-1.

The LC resonance circuit 222 to which a signal of resonance frequency issupplied from the signal generation circuit 224A as signal generatingmeans via the cable 223 is magnetic field forming means for forming aninduced magnetic field of resonance frequency by being induced by theinput resonance frequency signal, and function as a signal source forgenerating a signal for orientation detection (magnetic field in themodification) for specifying the orientation of the capsule medicaldevice 20A with respect to the reference direction Ds (that is, tilt ofthe specified direction Ui).

The LC resonance circuit 222 is fixed on the outside surface (forexample, the jacket 122 or the like) of the subject 900. The LCresonance circuit 222 is fixed to the outside surface of the subject 900so that the polarity direction of an inductor as a component of the LCresonance circuit 222 (corresponding to the symmetrical axis of amagnetic field distribution shape of the magnetic field generated by theLC resonance circuit 222) and the reference direction Ds become parallelto each other. Consequently, even in the case where the capsule medicaldevice 20A rotates using the center line in the longitudinal directionas an axis, the orientation of the specified direction Ui of the capsulemedical device 20A with respect to the reference direction Ds can bespecified on the basis of the phase, strength, and the like of themagnetic field detected by the magnetic sensors 23 a and 23 b of thecapsule medical device 20A.

In the modification 2-1, the reception signal supplied from the antenna120 to the transmitting/receiving circuit 131 is supplied to the signalprocessing circuit 132. In the modification 2-1, as described above, thesignal detection data is added to the image data received from thecapsule medical device 20A. The signal processing circuit 132 executes apredetermined process on the input signal (particularly, image data),specifies the signal detection data added to the image data, andsupplies it to the CPU 133A.

The CPU 133A functions as orientation specifying means estimatingspatial spread (magnetic field distribution) of the magnetic field fromthe LC resonance circuit 222 (sign for orientation detection) from theorientation and strength of the magnetic field (sign for orientationdetection) at the magnetic sensors 23 a and 23 b included in the signaldetection data and specifying the orientation with respect to thereference direction Ds of the capsule medical device 20A (that is,orientation with respect to the reference direction Ds of the specifieddirection Ui). Since the method of estimating the magnetic fielddistribution is similar to that of the modification 1-1, its detaileddescription will not be repeated.

As described above, in the modification 2-1, the LC resonance circuit222 as a signal source is fixed to the outside surface of the subject900, the magnetic sensors 23 a and 23 b as observation points aredisposed in the capsule medical device 20A, and orientation dataindicative of the orientation with respect to the reference direction Dsof the specified direction Ui is generated on the basis of the magneticfield from the LC resonance circuit 222 observed at the magnetic sensors23 a and 23 b. The other configuration is similar to any of those in theforegoing embodiments (including their modifications).

Next, the operation of the medical system 2A according to themodification 2-1 will be described in detail with reference to thedrawings. Since the operation of the display device 150 in themodification 2-1 is similar to that of the second embodiment, in thedescription, the operation of the capsule medical device 20A and thereceiving device 230A will be described below. FIG. 31 is a flowchartshowing an example of outline operation of the capsule medical device20A according to the modification 2-1. FIG. 32 is a flowchart showing anexample of outline operation of the receiving device 230A according tothe modification 2-1.

As shown in FIG. 31, after startup, the capsule medical device 20Aobtains image data by executing imaging operation periodically (forexample, at intervals of time T (0.5 second)) (steps S211-1 to S212-1).Subsequently, the capsule medical device 20A acquires time at which theimage data is obtained (step S213-1). The capsule medical device 20Areads detection signals from the magnetic sensors 23 a and 23 b by usingthe signal detection unit 21A, executes a predetermined signal process(step S214-1), and generates, as signal detection data, the strength andorientation at each of the magnetic sensors 23 a and 23 b of themagnetic field obtained (sign for orientation detection) (step S215-1).Subsequently, the capsule medical device 20A adds the acquisition timeas a time stamp to the image data and adds the generated signaldetection data to the image data (step S216-1). The capsule medicaldevice 20A transmits the image data to which the time stamp and thesignal detection data is added as a wireless signal (step S217-1) andreturns to step S211-1. By such operation, the image data to which thetime stamp and the signal detection data is added is periodicallytransmitted by radio from the capsule medical device 20A to thereceiving device 230A. The operations of the capsule medical device 20Ashown in FIG. 31 are continued until no power remains in the battery 16in the capsule medical device 20A.

On the other hand, the receiving device 230A always supplies the signalof the resonance frequency generated by the signal generation circuit224A to the LC resonance circuit 222, thereby generating the magneticfield as the sign for orientation detection from the LC resonancecircuit 222. In parallel with the operation, as shown in FIG. 32, forexample, the receiving device 230A always or periodically monitorswhether image data is received from the capsule medical device 20A (Noin step S221-1). In the case where image data is received (Yes in stepS221-1), the receiving device 230A supplies the signal detection dataincluded in the image data received to the CPU 133A, estimates spatialspread (magnetic field distribution) of the magnetic field from the LCresonance circuit 222, specifies the orientation with respect to thereference direction Ds of the capsule medical device 20A (that is,orientation with respect to the reference direction Ds of the specifieddirection Ui) in the CPU 133A, and generates it as orientation data(step S222-1).

Next, like the operation described with reference to FIG. 12 in thefirst embodiment, the receiving device 230A adds the orientation datagenerated in the CPU 133A to the image data received in step S221-1(step S223-1) and, as a result, either stores the image data to whichthe orientation data and the time stamp are added from the interface 137into the portable recording medium 140 or transmits the image data fromthe interface 137 to the display device 150 via the communication cable159 (step S224-1). After that, the receiving device 230A determineswhether the operation is continued, for example, whether an operationend instruction is received from the operation unit 135 (step S225-1).In the case of continuing the operation (Yes in step S225-1), thereceiving device 230A returns to step S221-1 and repeats output ofelectromagnetic wave (sign for orientation detection) and waiting forreception of next image data. On the other hand, in the case where theoperation is not continued (No in step S225-1), the operation isfinished.

With the configuration and operation as described above, in themodification 2-1, in a manner similar to the first or second embodiment(including its modification), the orientations of a plurality of piecesof image data can be aligned by performing the rotation correction onimage data on the basis of the orientation with respect to the referencedirection Ds of the capsule medical device 20A at the time of imaging,so that the medical system 2A and the image processing method enablingreduced time and effort on diagnosis and improved accuracy of adiagnosis result can be realized.

Modification 2-2

As the signal source in the second embodiment, an ultrasound generationsource can be used. In the following, this case will be described indetail as modification 2-2 of the second embodiment with reference tothe drawings. In the following description, the same reference numeralsare designated to components similar to those of the foregoingembodiment or its modification for simplification of explanation, andtheir description will not be repeated.

FIG. 33 is a schematic diagram showing a schematic configuration of amedical system 2B according to the modification 2-2. FIG. 34 is a blockdiagram showing a schematic configuration example of a capsule medicaldevice 20B and a receiving device 230B according to the modification2-2.

As shown in FIG. 33, in the medical system 2B, in comparison with themedical system 2 shown in FIG. 24, the capsule medical device 20 isreplaced with the capsule medical device 20B, and the receiving device230 is replaced with the receiving device 230B. Further, in the medicalsystem 2B, the receiving device 230B is provided with a plurality ofpiezoelectric elements 225 a and 225 b connected to the receiving device230B via a cable 226.

As shown in FIG. 34, in the capsule medical device 20B, in aconfiguration similar to that of the capsule medical device 20 shown inFIG. 25, the antennas 22 a and 22 b are replaced with a plurality ofacoustic sensors 24 a and 24 b, and the signal detection unit 21 isreplaced with a signal detection unit 21B.

Like the acoustic sensors 125 a and 125 b of the foregoing modification1-2, each of the acoustic sensors 24 a and 24 b is constructed by, forexample, a microphone and functions as an observation point asultrasound detecting means for observing a sign for orientationdetection (an ultrasound wave in the modification) generated from thepiezoelectric elements 225 a and 225 b as a signal source. Theinvention, however, is not limited to the sensors but, for example, apiezoelectric element or the like may be used.

The number and the arrangement pattern of the acoustic sensors 24 a and24 b can be variously modified as long as the number and the arrangementpattern by which the CPU 133B can estimate/specify the orientation ofthe capsule medical device 20B from the strength and phase of ultrasoundwaves generated by the piezoelectric elements 225 a and 225 b fixed tothe outer surface of the subject 900 are used. In the description, thenumber of the acoustic sensors 24 a and 24 b is at least two.

Preferably, the acoustic sensors 24 a and 24 b are fixed in the casing18 so that the arrangement direction coincides with the orientation ofthe specified direction Ui. Since the arrangement direction with respectto the reference direction Ds of the acoustic sensors 24 a and 24 b canbe used directly as the orientation with respect to the referencedirection Ds of the capsule medical device 20B (that is, the specifieddirection Ui), the process in the receiving device 230B which will bedescribed later can be lessened.

The signal detection unit 21B executes, on a detection signal suppliedfrom each of the acoustic sensors 24 a and 24 b, bandpass process and apredetermined process including a process of detecting the phase andstrength of an ultrasonic wave (a sign for orientation detection) in theacoustic sensors 24 a and 24 b. The signal detection unit 21B adds, assignal detection data, the detected phase, strength, and the like toimage data obtained at the same time or around the same time.

The signal detection data includes data corresponding to the phase andstrength of the ultrasonic wave (sign for orientation detection) in theacoustic sensors 125 a and 125 b detected by the signal detectioncircuit 131B in the receiving device 130B in the modification 1-2. Tothe image data, a time stamp is also added in a manner similar to themodification 1-2. The image data to which the signal detection data andthe time stamp are added is transmitted by radio from the antenna 15 ato the receiving device 230B from the processing unit 12B via thetransmitting/receiving unit 14.

On the other hand, the receiving device 230B has, as shown in FIG. 34,in addition to a configuration similar to the receiving device 230 shownin FIG. 25, a signal generation circuit 224B for supplying a signal ofresonance frequency to the piezoelectric elements 225 a and 225 b viathe cable 226. In the receiving device 230B, in a configuration similarto the receiving device 230 shown in FIG. 25, the antenna 220 and thetransmitting/receiving circuit 231 are replaced with the antenna 120 andthe transmitting/receiving circuit 131 in the first embodiment,respectively, and the CPU 133 is replaced with the CPU 133B in themodification 1-2.

The piezoelectric elements 225 a and 225 b to which the signal ofresonance frequency is supplied from the signal generation circuit 224Bas the signal generating means are ultrasound generating means forgenerating an ultrasound wave which vibrates by the input resonancefrequency signal and generates an ultrasonic wave and functions as asignal source generating a sign for orientation detection (theultrasound wave in the example) for specifying the orientation of thecapsule medical device 20B (that is, tilt of the specified direction Ui)with respect to the reference direction Ds.

Each of the piezoelectric elements 225 a and 225 b is fixed to thesurface (for example, the jacket 122 or the like) of the subject 900.The piezoelectric elements 225 a and 225 b are fixed to the outsidesurface of the subject 900 so that the arrangement direction of thepiezoelectric elements 225 a and 225 b and the reference direction Dsbecome parallel to each other. Even in the case where the capsulemedical device 20B rotates around the center line in the longitudinaldirection as an axis, the orientation of the specified direction Ui ofthe capsule medical device 20B with respect to the reference directionDs can be specified on the basis of the phase, strength, and the like ofthe ultrasound wave detected by the acoustic sensors 24 a and 24 b ofthe capsule medical device 20B.

In the modification 2-2, the reception signal supplied from the antenna120 to the transmitting/receiving circuit 131 is supplied to the signalprocessing circuit 132. In the modification 2-2, as described above, thesignal detection data is added to the image data received from thecapsule medical device 20B. The signal processing circuit 132 executes apredetermined process on the input signal (particularly, image data),specifies the signal detection data added to the image data, andsupplies it to the CPU 133B.

The CPU 133B functions as orientation specifying means estimatingspatial spread (ultrasound distribution) of the ultrasound wave (signfor orientation detection) from the piezoelectric elements 225 a and 225b from the phase and strength of the ultrasonic wave (sign fororientation detection) in the acoustic sensors 24 a and 24 b included inthe signal detection data and specifying the orientation with respect tothe reference direction Ds of the capsule medical device 20B (that is,the orientation with respect to the reference direction Ds of thespecified direction Ui). Since the method of estimating the ultrasonicwave distribution is similar to that of the modification 1-2, itsdetailed description will not be repeated.

As described above, in the modification 2-2, the piezoelectric elements225 a and 225 b as a signal source are fixed to the outside surface ofthe subject 900, the acoustic sensors 24 a and 24 b as observationpoints are disposed in the capsule medical device 20B, and orientationdata indicative of the orientation with respect to the referencedirection Ds of the specified direction Ui is generated on the basis ofthe ultrasound wave from the piezoelectric elements 225 a and 225 bobserved at the acoustic sensors 24 a and 24 b. The other configurationis similar to any of those in the foregoing embodiments (including theirmodifications).

Next, the operation of the medical system 2B according to themodification 2-2 will be described in detail with reference to thedrawings. Since the operation of the receiving device 230B and thedisplay device 150 in the modification 2-2 is similar to that of thesecond embodiment, in the description, the operation of the capsulemedical device 20B will be described below. The receiving device 230Bgenerates an ultrasound wave as a sign for orientation detection fromthe piezoelectric elements 225 a and 225 b by always supplying thesignal of the resonance frequency generated by the signal generationcircuit 224B to the piezoelectric elements 225 a and 225 b. FIG. 35 is aflowchart showing an example of outline operation of the receivingdevice 230B according to the modification 2-2.

As shown in FIG. 35, after startup, the capsule medical device 20Bobtains image data by executing imaging operation periodically (forexample, at intervals of time T (0.5 second)) (steps S211-2 to S212-2).Subsequently, the capsule medical device 20B acquires time at which theimage data is obtained (step S213-2). The capsule medical device 20Breads detection signals from the acoustic sensors 24 a and 24 b by usingthe signal detection unit 21B, executes a predetermined signal process(step S214-2), and generates, as signal detection data, the strength andphase at each of the acoustic sensors 24 a and 24 b of the receivedultrasonic wave (the sign for orientation detection) (step S215-2).Subsequently, the capsule medical device 20B adds the acquired time as atime stamp to the image data and adds the generated signal detectiondata to image data (step S216-2). Next, the capsule medical device 20Btransmits, as a wireless signal, image data to which the time stamp andthe signal detection data is added (step S217-2) and returns to stepS211-2. By the operation, the image data to which the time stamp and thesignal detection data is added is periodically transmitted by radio fromthe capsule medical device 20B to the receiving device 230B. Theoperation of the capsule medical device 20B shown in FIG. 35 iscontinued until no power remains in the battery 16 in the capsulemedical device 20B.

With the configuration and operation as described above, in themodification 2-2, in a manner similar to the first or second embodiment(including its modifications), the orientations of a plurality of piecesof image data can be aligned by performing the rotation correction onimage data on the basis of the orientation with respect to the referencedirection Ds of the capsule medical device 20B at the time of imaging,so that the medical system 2B and the image processing method enablingreduced time and effort on diagnosis and improved accuracy of adiagnosis result can be realized.

Third Embodiment

Although the case of setting the reference direction Ds in the subject900 and performing rotation correction on image data in accordance withan orientation relative to the subject 900 has been described as anexample in the foregoing embodiments (including their modifications),the invention is not limited to the case. The reference direction may beset out of the subject 900. Specifically, the reference direction usedat the time of performing rotation correction may be set to a systemindependent of the orientation and posture of the subject 900. Anexample of such a system is real space. In the following, the case ofsetting the reference direction Ds in the real space will be describedin detail as a third embodiment with reference to the drawings. In thefollowing description, the same reference numerals are designated tocomponents similar to those of the forgoing embodiment and itsmodifications for simplicity of explanation, and their detaileddescription will not be repeated.

FIG. 36 is a schematic diagram showing a schematic configuration of amedical system 3 according to the third embodiment. FIG. 37 is a blockdiagram showing an example of a schematic configuration of the capsulemedical device 10 and a receiving device 330 according to the thirdembodiment. In the third embodiment, the capsule medical device 10according to the first embodiment is used. The capsule medical device 10has the antenna 15 a having directivity.

As illustrated in FIG. 36, in the medical system 3, in comparison withthe medical system 1 shown in FIG. 1, the receiving device 130 isreplaced with the receiving device 330. The receiving device 330 ismounted on, for example, the floor so as not to move. The spaceincluding the floor is real space in which a reference direction Dg isset in the third embodiment.

Further, the medical system 3 has a sensor stand 320 mounted on thefloor surface so as not to move, a bed 341 on which the subject 900lies, and a movable stage 340 supporting the bed 341 so as to be movablein the horizontal direction. In the embodiment, the capsule medicaldevice 10 according to the first embodiment is used. The bed 341 may befixed to the floor surface so as not to move.

As shown in FIG. 37, the receiving device 330 has a configurationsimilar to that of the receiving device 130 shown in FIG. 5. Theantennas 120 connected to the receiving device 330 via the cable 121are, for example, arranged in a matrix on the sensor stand 320 fixed tothe receiving device 330 so as not to move relative to the floorsurface. The sensor stand 320 is mounted so that the face on which theantennas 120 are arranged faces the rear face of the bed 341. That is,the sensor stand 320 is mounted below the bed 341 in a state where theface on which the antennas 120 are arranged faces upward. The invention,however, is not limited to the arrangement but can be variously modifiedto, for example, the antennas 120 are disposed in the bed 341 so as tobe arranged on the mount face or the rear face of the bed 341.

By making the bed 341 horizontally movable, particularly, horizontallymovable with respect to the sensor stand 320, the position of thesubject 900 relative to the antennas 120, that is, the position of thecapsule medical device 10 can be properly adjusted. Thus, theorientation of the capsule medical device 10 can be specified withhigher precision.

As described above, in the third embodiment, by fixing the antennas 120as observation points in the real space, orientation data indicative ofthe orientation of the specified direction Ui with respect to thereference direction Dg set in the real space is generated. The otherconfiguration is similar to that of any of the foregoing embodiments(including their modifications). Since the operation of the medicalsystem 3 according to the embodiment is similar to that of the firstembodiment, the detailed description will not be repeated.

An example of the rotation correction according to the third embodimentand an example of the average color bar generated by using the imagedata subjected to the rotation correction according to the thirdembodiment will be described in detail with reference to the drawings.FIG. 38 is a diagram for explaining the rotation correction according tothe third embodiment. FIG. 39 is a diagram showing an example of theaverage color bar 60 generated by using the image data subjected to therotation correction according to the third embodiment.

As shown in (a) in FIG. 38, in image data Im31 obtained at the firstimaging timing, the specified direction Ui and the reference directionDg coincide with each other. Consequently, a rotation amount (correctionamount) B at the time of the rotation correction on the image data Im31is 0°. As shown in (b) in FIG. 38, in image data Im32 obtained at thesecond imaging timing, the angle of the specified direction Ui withrespect to the reference direction Dg is 90°. Therefore, the rotationamount (correction amount) B at the time of the rotation correction onthe image data Im32 is 90°. Further, as shown in (c) in FIG. 38, inimage data Im33 obtained at the third imaging timing, the angle of thespecified direction Ui with respect to the reference direction Dg is180°. Therefore, the rotation amount (correction amount) B at the timeof the rotation correction on the image data Im33 is 180°. The rotationcorrecting unit 154 a in the display device 150 of the embodimentperforms the rotation correction on the image data Im31 to Im33 on thebasis of the orientation data in a manner similar to the foregoingembodiments (including their modifications). Consequently, in image dataIm41 to Im43 subjected to the rotation correction, as shown in (d) to(f) in FIG. 38, the upward direction Du of the screen coincides with thereference direction Dg.

As a result of the rotation correction as described above, asillustrated in (d) to (f) in FIG. 38, the same part p1 in image dataIm41 to Im43 is included in the same division region A3. Consequently,as shown in FIG. 39, the positions of regions P21 to P23 including thesame part p1 in the average color bar 60 generated by using the imagedata Im41 to Im43 subjected to the rotation correction can be aligned inthe horizontal direction in the division region A3. (d) in FIG. 38 showsthe image data Im41 obtained by rotation-correcting the image data Im31of (a) in FIG. 38, (e) in FIG. 38 shows the image data Im42 obtained byrotation-correcting the image data Im32 of (b) in FIG. 38, and (f) inFIG. 38 shows the image data Im43 obtained by rotation-correcting theimage data Im33 of (c) in FIG. 38.

Also in the third embodiment, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

With the configuration and operation as described above, in the thirdembodiment, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Dg of the capsulemedical device 10 at the time of imaging, so that the medical system 3and the image processing method enabling reduced time and effort ondiagnosis and improved accuracy of a diagnosis result can be realized.

Also in the third embodiment, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

Modification 3-1

Although the case of using the electromagnetic wave generating source(antenna 15 a) as the signal source has been described as an example inthe medical system 3 according to the third embodiment, the invention isnot limited to the case but a magnetic field generating source can beused as the signal source. The case will be described in detail below asmodification 3-1 of the third embodiment with reference to the drawings.In the following description, the case of specifying the orientation ofthe capsule medical device 10A′ by a so-called passive method of makingan LC resonance circuit 17 b mounted on the capsule medical device 10A′excite by using an external magnetic field (drive magnetic field) togenerate an induced magnetic field will be taken as an example. In thefollowing description, the same reference numerals are designated tocomponents similar to those of any of the foregoing embodiments andtheir modifications for simplicity of explanation, and their detaileddescription will not be repeated.

FIG. 40 is a schematic diagram showing a schematic configuration of amedical system 3A according to the modification 3-1. FIG. 41 is a blockdiagram showing a a schematic configuration example of the capsulemedical device 10A and a receiving device 330A. In the modification 3-1,the capsule medical device 10A′ in the modification 1-1 is used. Thecapsule medical device 10A′ has, as a signal source, the LC resonancecircuit 17 b generating an induced magnetic field when induced by theexternal magnetic field (drive magnetic field) of a predeterminedresonance frequency.

As shown in FIG. 40, in the medical system 3A, as compared with themedical system 3 shown in FIG. 36, the capsule medical device 10 isreplaced with the capsule medical device 10A, and the receiving device330 is replaced with the receiving device 330A. The receiving device330A is mounted, for example, on the floor or the like so as not to movelike the receiving device 330. In the periphery of a part (hereinbelow,called detection space K) in the space in which the subject 900 on thebed 341 is mounted, total three sets of drive coils Dx_1 and Dx_2, Dy_1and Dy_2, and Dz_1 and Dz_2, opposed in the x axis, y axis, and z axisare disposed. In the following, the reference numeral of an arbitrarydrive coil will be called D, and reference numerals of drives coils ofan arbitrary pair will be called D_1 and D_2.

Further, the medical system 3A has the sensor stand 320 mounted so asnot to move relative to the floor face and a plurality of magneticsensors S_1 to S_8 arranged in a matrix, for example, on the sensorstand 320 so as not to move relative to the floor face. In thefollowing, the reference numeral of an arbitrary magnetic sensor will beS. The sensor stand 320 is mounted so that the face on which themagnetic sensors S are arranged is adjacent to the detection space K.For example, the sensor stand 320 is mounted over the detection space Kin a state where the face on which the magnetic sensors S are arrangedfaces downward. The invention, however, is not limited to thearrangement but can be variously modified such as a case that theantennas 120 are disposed in the bed 341 so as to be arranged on themount face or the rear face of the bed 341.

As shown in FIG. 41, in the receiving device 330A, in a configurationsimilar to that of the receiving device 330 shown in FIG. 37, the CPU133 is replaced with the CPU 133A. Further, the receiving device 330Ahas a coil drive unit 331A for generating a drive signal almost equal tothe resonance frequency of the LC resonance circuit 17 b and supplyingit to the drive coil D, and a signal detection unit 332A for reading apotential change which occurs in any of the magnetic sensors S as adetection signal.

The drive coil D generates a drive magnetic field of an almost resonancefrequency in the detection space K by the drive signal input from thecoil drive unit 331A. Each of the magnetic sensors S is influenced by aninduced magnetic field generated when the LC resonance circuit 17 b ofthe capsule medical device 10A′ is excited by the drive magnetic fieldgenerated in the detection space K, and changes its potential. Thepotential change occurring in each of the magnetic sensors S depends onthe position and orientation of each of the magnetic sensors S disposedand the position and orientation of the LC resonance circuit 17 b.

The signal detection unit 332A reads, as a detection signal, a potentialchange occurring in each of the magnetic sensors S via the cable 121,executes a predetermined process such as frequency separation or FFTand, after that, supplies the processed detection signal as orientationdata to the CPU 133A.

Like the CPU 133 in the foregoing first embodiment, the CPU 133Afunctions as orientation specifying means specifying the orientation ofthe capsule medical device 10A′ (that is, tilt of the specifieddirection Ui) with respect to the reference direction Dg from thestrength and orientation of the sign (magnetic field) for orientationdetection observed at the observation points (the magnetic sensors S_1to S_8). That is, the CPU 133A estimates the spatial spread of themagnetic field (magnetic field distribution) on the basis of themagnetic field strength of a detection signal, the orientation of a lineof magnetic force, and the like in each of the magnetic sensors Ssupplied from the signal detection circuit 332A and specifies theorientation with respect to the reference direction Dg of the capsulemedical device 10A′ (that is, the orientation with respect to thereference direction Dg of the specified direction Ui). In a mannersimilar to the foregoing embodiments, information of the orientation(orientation data) with respect to the reference direction Dg of thespecified direction Ui specified by the CPU 133A is temporarily storedin association with image data received simultaneously or around thesame time from the capsule medical device 10A′ into the memory 134.

In such a manner, in the modification 3-1, by fixing the magnetic sensorS as the observation point in the real space, orientation dataindicative of the orientation of the specified direction Ui with respectto the reference direction Dg which is set for the real space isgenerated. The other configuration is similar to that of any of theforegoing embodiments (including their modifications). Since theoperation of the medical system 3A according to the embodiment issimilar to that of the modification 1-1, the detailed description willnot be repeated.

With the configuration and operation as described above, in themodification 3-1, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Dg of the capsulemedical device 10A′ at the time of imaging, so that the medical system3A and the image processing method enabling reduced time and effort ondiagnosis and improved accuracy of a diagnosis result can be realized.

Also in the modification 3-1, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

Modification 3-2

As the signal source in the third embodiment, an ultrasound generationsource can be also used. In the following description, the samereference numerals are designated to components similar to those of anyof the foregoing embodiments and their modifications for simplicity ofexplanation, and their detailed description will not be repeated.

FIG. 42 is a schematic diagram showing a schematic configuration of amedical system 3B according to the modification 3-2. FIG. 43 is a blockdiagram showing a schematic configuration example of the capsule medicaldevice 10B and a receiving device 330B according to the modification3-2. In the modification 3-2, the capsule medical device 10B in themodification 1-2 is used. The capsule medical device 10B has, as asignal source, the piezoelectric elements 17 c and 17 d generating anultrasonic wave propagating in the subject 900 and reaching the outersurface.

As shown in FIG. 42, in the medical system 3B, as compared with themedical system 3 shown in FIG. 36, the capsule medical device 10 isreplaced with the capsule medical device 10B, and the receiving device330 is replaced with the receiving device 330B. The receiving device330B is mounted, for example, on the floor or the like so as not to movelike the receiving device 330. Near the face which comes into contactwith the subject 900 in the bed 341, acoustic sensors 125 a to 125 iconnected to the receiving device 330B via the cable 126.

As shown in FIG. 43, in the receiving device 330B, in a configurationsimilar to that of the receiving device 330 shown in FIG. 37, the CPU133 is replaced with the CPU 133B. Further, the receiving device 330Bhas a signal detection unit 332B for reading, as a detection signal, apotential change which occurs in any of the acoustic sensors 125 a to125 i as a detection signal.

The signal detection unit 332B reads, as a detection signal, a potentialchange occurring in each of the acoustic sensors 125 a to 125 i via thecable 126, executes a predetermined process such as frequency separationor FFT and, after that, supplies the processed detection signal asorientation data to the CPU 133B.

Like the CPU 133 in the foregoing first embodiment, the CPU 133Bfunctions as orientation specifying means specifying the orientation ofthe capsule medical device 10B (that is, tilt of the specified directionUi) with respect to the reference direction Dg from the strength andorientation of the sign (ultrasonic wave) for orientation detectionobserved at the observation points (the acoustic sensors 125 a to 125i). That is, the CPU 133B estimates the spatial spread of the ultrasonicwave (ultrasound distribution) from the strength, phase, and the like ofdetection signals at the acoustic sensors 125 a to 125 i supplied fromthe signal detection circuit 332B and specifies the orientation withrespect to the reference direction Dg of the capsule medical device 10B(that is, the orientation with respect to the reference direction Dg ofthe specified direction Ui) from arrangement of the piezoelectricelements 17 c and 17 d. In a manner similar to the foregoingembodiments, information of the orientation (orientation data) withrespect to the reference direction Dg of the specified direction Uispecified by the CPU 133B is temporarily stored in association withimage data received simultaneously or around the same time from thecapsule medical device 10B into the memory 134.

In such a manner, in the modification 3-2, by fixing the acousticsensors 125 a to 125 i as the observation points in the real space,orientation data indicative of the orientation of the specifieddirection Ui with respect to the reference direction Dg which is set forthe real space is generated. The other configuration is similar to thatof any of the foregoing embodiments (including their modifications).Since the operation of the medical system 3B according to the embodimentis similar to that of the modification 1-2, the detailed descriptionwill not be repeated.

With the configuration and operation as described above, in themodification 3-2, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Dg of the capsulemedical device 10B at the time of imaging, so that the medical system 3Band the image processing method enabling reduced time and effort ondiagnosis and improved accuracy of a diagnosis result can be realized.

Also in the modification 3-2, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

Fourth Embodiment

Although the case of disposing the signal source (antenna 15 a) in thecapsule medical device 10 and fixing the observation points (antennas120) in the real space has been described as an example in the thirdembodiment, the invention is not limited to the case. It is alsopossible to fix the signal source in the real space and dispose theobservation points in the capsule medical device. In the following, thecase will be described in detail as a fourth embodiment with referenceto the drawings. In the following description, the same referencenumerals are designated to components similar to those of the forgoingembodiment and its modifications for simplicity of explanation, andtheir detailed description will not be repeated.

FIG. 44 is a schematic diagram showing a schematic configuration of amedical system 4 according to the fourth embodiment. FIG. 45 is a blockdiagram showing an example of a schematic configuration of the capsulemedical device 20 and a receiving device 430 according to the fourthembodiment. In the fourth embodiment, the capsule medical device 20according to the second embodiment is used. The capsule medical device20 has the plurality of antennas 22 a and 22 b.

As illustrated in FIG. 44, in the medical system 4, in comparison withthe medical system 2 shown in FIG. 24, the receiving device 230 isreplaced with the receiving device 430. The receiving device 430 ismounted on, for example, the floor so as not to move. The spaceincluding the floor is real space in which a reference direction Dg isset in the fourth embodiment. Further, the medical system 4 has a sensorstand mounted on the floor surface so as not to move, the bed 341 onwhich the subject 900 lies, and the movable stage 340 supporting the bed341 so as to be movable in the horizontal direction. The bed 341 may befixed to the floor surface so as not to move.

As shown in FIG. 45, the receiving device 430 has a configurationsimilar to that of the receiving device 230 shown in FIG. 25. Theantennas 220 connected to the receiving device 430 via the cable 221are, for example, disposed on the sensor stand fixed to the receivingdevice 430 so as not to move relative to the floor surface. The sensorstand 320 is mounted so that the face on which the antennas 220 arearranged faces the rear face of the bed 341. That is, the sensor stand320 is mounted below the bed 341 in a state where the face on which theantennas 220 are arranged faces upward. The invention, however, is notlimited to the arrangement but can be variously modified to, forexample, a case where the antennas 220 are disposed in the bed 341 so asto be arranged on the mount face or the rear face of the bed 341.

By making the bed 341 horizontally movable, particularly, horizontallymovable with respect to the sensor stand 320, the position of thesubject 900 relative to the antennas 220, that is, the position of thecapsule medical device 20 can be properly adjusted. Thus, theorientation of the capsule medical device 20 can be specified withhigher precision.

As described above, in the fourth embodiment, by fixing the antenna 220as the signal source in the real space, orientation data indicative ofthe orientation of the specified direction Ui with respect to thereference direction Dg set in the real space is generated. The otherconfiguration is similar to that of any of the first embodiment(including its modifications), the second embodiment (including itsmodifications), and the third embodiment (including its modifications).Since the operation of the medical system 4 according to the embodimentis similar to that of the second embodiment, the detailed descriptionwill not be repeated.

With the configuration and operation as described above, in the fourthembodiment, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Dg of the capsulemedical device 20 at the time of imaging, so that the medical system 4and the image processing method enabling reduced time and effort ondiagnosis and improved accuracy of a diagnosis result can be realized.

Also in the fourth embodiment, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

Modification 4-1

Although the case of using the electromagnetic wave generating source(antenna 220) as the signal source has been described as an example inthe medical system 4 according to the fourth embodiment, the inventionis not limited to the case but a magnetic field generating source can beused as the signal source. The case will be described in detail below asmodification 4-1 of the fourth embodiment with reference to thedrawings. In the following description, the case of specifying theorientation of the capsule medical device 20A by a so-called activemethod of supplying a signal (drive signal) of the resonance frequencyto the LC resonance circuit 222 fixed in the real space to make the LCresonance circuit 222 generate an induced magnetic field will be takenas an example. In the following description, the same reference numeralsare designated to components similar to those of any of the foregoingembodiments and their modifications for simplicity of explanation, andtheir detailed description will not be repeated.

FIG. 46 is a schematic diagram showing a schematic configuration of amedical system 4A according to the modification 4-1. FIG. 47 is a blockdiagram showing a schematic configuration example of the capsule medicaldevice 20A and a receiving device 430A in the modification 4-1. In themodification 4-1, the capsule medical device 20A in the modification 2-1is used. The capsule medical device 20A has a plurality of magneticsensors 23 a and 23 b as observation points.

As shown in FIG. 46, in the medical system 4A, as compared with themedical system 4 shown in FIG. 44, the capsule medical device 20 isreplaced with the capsule medical device 20A, the receiving device 430is replaced with the receiving device 430A, and the antenna 220 of thereceiving device 430 is replaced with the sensor stand 320 and theantenna 120. The receiving device 430A is mounted, for example, on thefloor or the like so as not to move. To the bed 341, the LC resonancecircuit 222 as the signal source is fixed. The LC resonance circuit 222is connected to the receiving device 430A via the cable 223.

As shown in FIG. 47, the receiving device 430A has, in addition to theconfiguration similar to that of the receiving device 430 shown in FIG.45, a signal generation circuit 224A. In the receiving device 430A, in aconfiguration similar to the receiving device 430 shown in FIG. 45, theantenna 220 and the transmitting/receiving circuit 231 are replaced withthe antenna 120 and the transmitting/receiving circuit 131, and the CPU133 is replaced with the CPU 133A. That is, the receiving device 430Ahas a configuration almost similar to that of the receiving device 230Ain the modification 2-1 except for the point that the antenna 120 andthe LC resonance circuit 222 are fixed to the sensor stand 320, the bed341, and the like.

That is, the CPU 133A specifies the orientation with respect to thereference direction Dg of the capsule medical device 20A (that is, thetilt of the specified direction Ui) by using the signal detection dataadded to the image data from the capsule medical device 20A.

In such a manner, in the modification 4-1, by fixing the LC resonancecircuit 222 as the signal source in the real space, orientation dataindicative of the orientation of the specified direction Ui with respectto the reference direction Dg which is set for the real space isgenerated. The other configuration is similar to that of any of theforegoing embodiments (including their modifications). Since theoperation of the medical system 4A according to the modification 4-1 issimilar to that of the modification 2-1, the detailed description willnot be repeated.

With the configuration and operation as described above, in themodification 4-1, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Dg of the capsulemedical device 20A at the time of imaging, so that the medical system 4Aand the image processing method enabling reduced time and effort ondiagnosis and improved accuracy of a diagnosis result can be realized.

Also in the modification 4-1, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

Modification 4-2

As the signal source in the fourth embodiment, an ultrasound generationsource can be also used. This case will be described in detail below asmodification 4-2 of the fourth embodiment with reference to thedrawings. In the following description, the same reference numerals aredesignated to components similar to those of any of the foregoingembodiments and their modifications for simplicity of explanation, andtheir detailed description will not be repeated.

FIG. 48 is a schematic diagram showing a schematic configuration of amedical system 4B according to the modification 4-2. FIG. 49 is a blockdiagram showing a schematic configuration example of the capsule medicaldevice 20B and a receiving device 430B according to the modification4-2. In the modification 4-2, the capsule medical device 20B in themodification 2-2 is used. The capsule medical device 20B has a pluralityof acoustic sensors 24 a and 24 b as observation points.

As shown in FIG. 48, in the medical system 4B, as compared with themedical system 4 shown in FIG. 44, the capsule medical device 20 isreplaced with the capsule medical device 20B, and the receiving device430 is replaced with the receiving device 430B, and the antenna 220 ofthe receiving device 430 is replaced with the sensor stand 320 and theantenna 120. The receiving device 430B is mounted, for example, on thefloor or the like so as not to move. Near the face which comes intocontact with the subject 900 in the bed 341, a plurality ofpiezoelectric elements 225 a and 225 b connected to the receiving device430B via the cable 226 (refer to FIG. 49) are disposed.

As shown in FIG. 48, the receiving device 430B has, in addition to aconfiguration similar to that of the receiving device 430 shown in FIG.45, the signal generation circuit 224B. In the receiving device 430B, ina configuration similar to that of the receiving device 430 shown inFIG. 45, the antenna 220 and the transmitting/receiving circuit 231 arereplaced with the antenna 120 and the transmitting/receiving circuit131, respectively. That is, the receiving device 430B has aconfiguration similar to that of the receiving device 230B according tothe modification 2-2 except for the point that the antenna 120 and theLC resonance circuit are fixed to the sensor stand 320, the bed 341, andthe like.

Therefore, the CPU 133 specifies the orientation with respect to thereference direction Dg of the capsule medical device 20B (that is, thetilt of the specified direction Ui) by using the signal detection dataadded to the image data from the capsule medical device 20B.

In such a manner, in the modification 4-2, by fixing the plurality ofpiezoelectric elements 225 a and 225 b as a signal source in the realspace, orientation data indicative of the orientation of the specifieddirection Ui with respect to the reference direction Dg which is set forthe real space is generated. The other configuration is similar to thatof any of the foregoing embodiments (including their modifications).Since the operation of the medical system 4B according to themodification 4-2 is similar to that of the modification 2-2, thedetailed description will not be repeated.

With the configuration and operation as described above, in themodification 4-2, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Dg of the capsulemedical device 20B at the time of imaging, so that the medical system 4Band the image processing method enabling reduced time and effort ondiagnosis and improved accuracy of a diagnosis result can be realized.

Also in the modification 4-2, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

Fifth Embodiment

Although a configuration of generating any signal, such as the antenna220, the LC resonance circuit 222, the piezoelectric elements 225 a and225 b disposing any signal source is used as the signal source fixed inthe real space in the fourth embodiment (including its modifications),the invention is not limited to the configuration. A physical phenomenonexisting in the real space such as gravity, geomagnetism, or the likemay be used. In the following, the case of using gravity in place of thesignal source will be described in detail with reference to thedrawings. In the following description, the same reference numerals aredesignated to components similar to those of the forgoing embodiment andits modifications for simplicity of explanation, and their detaileddescription will not be repeated.

FIG. 50 is a schematic diagram showing a schematic configuration of amedical system 5 according to the fifth embodiment. FIG. 51 is a blockdiagram showing an example of a schematic configuration of a capsulemedical device 50 and a receiving device 530 according to the fifthembodiment.

As shown in FIG. 50, in the medical system 5, in comparison with themedical system 1 shown in FIG. 1, the capsule medical device 10 isreplaced with the capsule medical device 50, and the receiving device130 is replaced with the receiving device 530.

As shown in FIG. 51, the capsule medical device 50 has, in addition to aconfiguration similar to that of the capsule medical device 10 shown inFIG. 5, a gravity sensor 51.

The gravity sensor 51 is gravity direction detecting means for detectingthe direction of gravity. Any acceleration sensor which can detectgravity and is small enough to be housed in the capsule medical device50 such as a mechanical acceleration sensor using a coil, a spring, aplate, or the like, a semiconductor-type acceleration sensor using theMicro Electro Mechanical Systems (MEMS) technique, or the like may beused.

A processing unit 52 reads a voltage change occurring in the gravitysensor 51 as a detection signal and executes a predetermined process onthe detection signal. The processing unit 52 adds, as orientation data,the detection signal subjected to the signal process to image dataobtained at the same time or around the same time.

As the orientation data, data expressing the direction of gravity usingthe capsule medical device 50 as a reference by a vector can be used. Byusing the data expressing the direction of gravity by a vector(orientation data), the orientation of the capsule medical device 50with respect to the reference direction Dg (that is, the orientation ofthe specified direction Ui with respect to the reference direction Dg)can be directly derived.

The present invention is not limited to the case. For example, bysetting one of three axes of the gravity sensor in a directionperpendicular to the light reception face, a gravity sensor of two axeswithout the axis can be used as the gravity sensor 51. To the imagedata, a time stamp is also added in a manner similar to the firstembodiment. The image data to which the signal detection data and thetime stamp are added is transmitted by radio from the processing unit 52via the transmitting/receiving unit 14 from the antenna 15 a to thereceiving device 530.

On the other hand, in the receiving device 530, as shown in FIG. 51, ina configuration similar to that of the receiving device 130 shown inFIG. 5, the signal processing circuit 132 is replaced with a signalprocessing circuit 532.

In the fifth embodiment, as described above, to image data received fromthe capsule medical device 50, the vector of the direction of gravitydetected by the gravity sensor 51 is added as the orientation data.Therefore, in the fifth embodiment, the signal processing circuit 532temporarily buffers the image data to which the input orientation dataand the time stamp are added in the memory 134 or the like and, afterthat, transmits the image data as it is to the display device 150 viathe interface 137.

As described above, in the fifth embodiment, the gravity which is stablein the real space is used as the sign for orientation detection, thegravity sensor 51 as the measurement point is disposed in the capsulemedical device 50, and the orientation data indicative of theorientation with respect to the reference direction Ds of the specifieddirection Ui is generated on the basis of the vector of the direction ofgravity measured by the gravity sensor 51. The other configuration issimilar to that of any of the foregoing embodiments (including theirmodifications).

Next, the operation of the medical system 5 according to the fifthembodiment will now be described in detail with reference to thedrawings. Since the operation of the display device 150 in the fifthembodiment is similar to that of the first embodiment, in theexplanation, the operation of the capsule medical device 50 and thereceiving device 530 will be described below. FIG. 52 is a flowchartshowing an example of schematic operation of the capsule medical device50 according to the fifth embodiment. FIG. 53 is a flowchart showing anexample of schematic operation of the receiving device 530 according tothe fifth embodiment.

As shown in FIG. 52, after startup, the capsule medical device 50executes imaging operation periodically (for example, at time T (=0.5second) intervals), thereby obtaining image data (steps S511 to S512).Subsequently, the capsule medical device 50 obtains time at which theimage data is obtained (step S513). The capsule medical device 50obtains a value detected by the gravity sensor 51 as orientation data(step S514). Subsequently, the capsule medical device 50 adds theobtained time as a time stamp to the image data and adds the obtainedorientation data to the image data (step S515). Next, the capsulemedical device 50 transmits, as a wireless signal, the image data towhich the time stamp and the orientation data is added (step S516), andreturns to the step S511. By such operation, the image data to which thetime stamp and the orientation data is added is periodically transmittedby radio from the capsule medical device 50 to the receiving device 530.The operation of the capsule medical device 50 shown in FIG. 52 iscontinued until no power remains in the battery 16 in the capsulemedical device 50.

On the other hand, as shown in FIG. 53, the receiving device 530, forexample, always or periodically, monitors whether image data is receivedfrom the capsule medical device 50 (No in step S521). In the case whereimage data is received (Yes in step S521), the receiving device 530temporarily buffers the received image data in the memory 134 or thelike and, after that, either stores the image data into the portablerecording medium 140 from the interface 137 or transmits the image datafrom the interface 137 to the display device 150 via the communicationcable 159 (step S522). After that, the receiving device 530 determineswhether the operation is continued, for example, whether an operationend instruction is received from the operation unit 135 (step S523). Inthe case of continuing the operation (Yes in step S523), the receivingdevice 530 returns to step S521 and repeats waiting of reception ofimage data. On the other hand, in the case where the operation is notcontinued (No in step S523), the operation is finished.

With the configuration and operation as described above, in the fifthembodiment, in a manner similar to the first embodiment, theorientations of a plurality of pieces of image data can be aligned byperforming the rotation correction on image data on the basis of theorientation with respect to the reference direction Ds (gravitydirection) of the capsule medical device 50 at the time of imaging, sothat the medical system 5 and the image processing method enablingreduced time and effort on diagnosis and improved accuracy of adiagnosis result can be realized.

In the fifth embodiment, in the case of setting the reference directionDg in the real space, the gravity can be used in place of the sign fororientation detection. As a result, using the gravity sensor 51 capableof detecting the gravity as almost the absolute reference which is notinfluenced by the posture and orientation of the subject 900, theorientation of the specified direction Ui with respect to the referencedirection Dg can be detected directly. Thus, the configuration fororientation detection can be simplified, and the process in thereceiving device 530 which will be described later can be lessened.

Also in the fifth embodiment, in a manner similar to the firstembodiment (including its modifications) and the second embodiment(including its modifications), the reference direction Ds set for thesubject 900 and the specified direction Ui can be made coincide witheach other. It can be realized that, for example, by manually enteringthe posture of the subject 900 by the observer or by providing thesubject 900 with a gravity sensor and performing automatic detection, atilt (rotation amount) between the reference direction Ds set for thesubject 900 and the reference direction Dg is obtained and, using thetilt (rotation amount) and the orientation (correction amount B) of thespecified direction Ui with respect to the reference direction Dg, imagedata is rotation-corrected.

Sixth Embodiment

In the foregoing embodiments (including their modifications), the caseof generating an image of the average color bar 60 from image dataobtained by performing rotation correction on image data and assemblingthe generated average color bar 60 in a GUI screen (refer to FIG. 8) forproviding the observer with the GUI function has been described. In thepresent invention, however, the image incorporated in the GUI screen isnot limited to the average color bar 60. In the following, an image of ared detection result (hereinbelow, called a red indicator) will be takenas an example and will be described in detail as a sixth embodiment withreference to the drawings. In the following description, the sixthembodiment will be described using the first embodiment as a base. Theinvention, however, is not limited to the case. Obviously, the sixthembodiment can be applied to any of the foregoing embodiments and theirmodifications.

The red detection is detection of the region (width) and density of redin image data. Therefore, by visualizing a result of red detection onimage data, the observer can visually recognize the amount and densityof red included in the image data. By generating and displaying a GUI(red indicator) in which images of the red detection results arearranged along the time series of the image data), the observer cangrasp a place where red appears most at a glance. As a result, theobserver can easily find a region of bleeding, swelling, or the like.

A medical system according to the sixth embodiment is obtained byreplacing the display device 150 (refer to FIG. 7) in the medical system1 shown in FIG. 1 with a display device 650 shown in FIG. 54. FIG. 54 isa block diagram showing a schematic configuration example of the displaydevice 650 according to the sixth embodiment. As obvious from comparisonbetween FIGS. 54 and 7, in the display device 650, the image processingunit 154 in the display device 150 is replaced with an image processingunit 654.

As shown in FIG. 54, the image processing unit 654 has a configurationsimilar to that of the image processing unit 154 except that a reddetecting unit 654 a and a red indicator generating unit 654 b are addedand the screen generating unit 154 e is replaced with a screengenerating unit (screen generating means) 654 e.

The red detecting unit 654 a functions as red detecting means fordetecting a red component included in image data subjected to rotationcorrection. Specifically, the red detecting unit 654 a determines theamount and density of a red component included in image data subjectedto the rotation correction selected by the image selecting unit 154 c,and generates red data obtained by averaging them. The determination andaveraging of the amount and density of the red component can be executedby using, for example, the value of the red component in the image data.The red detection may be performed in each of a plurality of (forexample, four) division regions (for example, division regions A1 to A4)obtained by dividing the image data.

The red data generated by the red detecting unit 654 a is supplied as ared detection result to the red indicator generating unit 654 b. The redindicator generating unit 654 b is red image generating means forgenerating an image (red image) visually displaying a detection resultof the red detecting unit 654 a. In the embodiment, as a red image, ared indicator (refer to a red indicator 66 in FIG. 56) is used.Therefore, the red indicator generating unit 654 b generates an image ofthe red indicator by using the red detection result and supplies theimage to the screen generating unit 654 e.

The screen generating unit 654 e generates a GUI screen as shown in FIG.56 by using image data subjected to rotation correction which isselected by the image selecting unit 154 c, an image of the averagecolor bar supplied from the average color bar generating unit 154 d, andan image of the red indicator input from the red indicator generatingunit 654 b. The GUI screen generated according to the sixth embodimentwill be described later.

Using FIG. 55, the operation of the display device 650 according to thesixth embodiment will be described in detail. As shown in FIG. 55,first, the display device 650 takes steps similar to the steps describedby using the steps S121 to S127 in FIG. 13 in the first embodiment,thereby executing the rotation correction on all of image data selected,and the process of generating an image of an average color bar. Next,the display device 650 executes a red detecting process in the reddetecting unit 654 a (step S621) and, subsequently, executes a processof generating an image of the red indicator from the red detectionresult in the red indicator generating unit 654 b (step S622).

Next, the display device 650 makes the screen generating unit 654 eexecute the screen generating process for generating a GUI screen asshown in FIG. 56 by using the image data subjected to the rotationcorrection, selected in the image selecting unit 154 c, the image of theaverage color bar supplied from the average color bar generating unit154 d, and an image of the red indicator supplied from the red indicatorgenerating unit 654 b (step S623) and, after that, finishes the process.The generated GUI screen is supplied to the display unit 155 via thecontrol unit 151 and displayed to the observer. As a result, theobserver is provided with the GUI function using the GUI screen and theinput unit 156.

Using FIG. 56, the GUI screen generated by the screen generating unit654 e will be described in detail. As shown in FIG. 56, in the GUIscreen generated by the screen generating unit 654 e, like the GUIscreen (refer to FIG. 8) generated by the screen generating unit 154 ein the foregoing embodiments, patient information g11, diagnosisinformation g12, a main image display region g13, a sub image displayregion g14, a reproduction control button g15, and an average color bar60 are incorporated. In the GUI screen, a red indicator 66 and a sliderg61 a indicative of the position on the average color bar 60 and the redindicator 66 in an image being displayed in the main image displayregion g13 while linking the average color bar 60 and the red indicator66 are incorporated.

The length in the time base direction of the red indicator 66 is thesame as that of the average color bar 60, and the red indicator 66 isdisposed above or below the average color bar 60 in the screen. With thearrangement, the time base of the average color bar 60 and that of thered indicator 66 can be linked in appearance, so that it enables theobserver to easily recognize a region in the average color bar 60, inwhich red appears often.

The color in a region corresponding to each of image data pieces in thered indicator 66 is graded according to the red detection result.Consequently, the observer can easily recognize a region in which redappears more often.

Modification 6-1

In the sixth embodiment, the case of visually displaying the reddetection result by using the red indicator 66 (refer to FIG. 56)expressing the red detection result by a bar-shaped image has beendescribed as an example. The present invention is not limited to thecase but, for example, as shown in FIG. 57, the red detection result maybe superimposed on the average color bar. FIG. 57 is a diagram showingan example of an average color bar 60_1 according to the modification6-1 of the sixth embodiment. The average color bar 60_1 is obtained bysuperimposing an image expressing a red detection result by a histogramin the average color bar 60. Therefore, in the image of the reddetection result, as shown in FIG. 57, the amount and density of red inimage data is expressed by the height. The invention, however, is notlimited to the expression. The red detection result may be expressed bya polygonal line.

For example, an image of the red detection result of image in which nored is detected or an average value of red data is smaller than a firstthreshold which is the minimum value is not drawn in the average colorbar 60_1. An image of the red detection result of image data smallerthan a second threshold as an intermediate value which is equal to orlarger than the first threshold is superimposed in the lowest divisionregion A1 in the corresponding image data part in the average color bar60_1. Further, an image of the red detection result on image data inwhich the average value of red data is equal to or larger than thesecond threshold as the maximum value is superimposed in the entirecorresponding image data part in the average color bar 60_1.

Modification 6-2

In the case of executing the red detection in each of the divisionregions A1 to A4 obtained by dividing image data into a plurality of(for example, four) pieces, images of the red detection results in thedivision regions A1 to A4 may be superimposed in an average color bar60_2 in association with the division regions A1 to A4 dividing imagedata as shown in FIG. 58. With the arrangement, the observer canvisually easily recognize a part in a region in which red is widelydetected. FIG. 58 is a diagram showing an example of the average colorbar 60_2 according to modification 6-2 of the sixth embodiment. Theaverage color bar 60_2 is obtained by superimposing an image of the reddetection result on the average color bar 60.

Modification 6-3

In the case of executing the red detection in each of the divisionregions A1 to A4 obtained by dividing image data into a plurality of(for example, four) pieces, images of the red detection results in thedivision regions A1 to A4 may be obtained by expressing the gradation ofthe red detection results on the division regions A1 to A4 by density ofred. Further, images of the red detection results in the divisionregions A1 to A4 may be superimposed in an average color bar 60_3 inassociation with the division regions A1 to A4 dividing image data asshown in FIG. 59. With the arrangement, the observer can visually easilyrecognize density of red in a part in a region. FIG. 59 is a diagramshowing an example of the average color bar 60_3 according tomodification 6-3 of the sixth embodiment. The average color bar 60_3 isobtained by superimposing an image of the red detection result on theaverage color bar 60.

Seventh Embodiment

In the sixth embodiment (including its modifications), an image of a reddetection result is linked and displayed on the average color bar 60. Inthe invention, an object which is linked and displayed on the averagecolor bar is not limited to the red detection result. For example, arotation amount used in the rotation correcting unit 154 a can be alsoused. In the following, an example of this case will be described indetail with reference to the drawings as a seventh embodiment. In thefollowing description, the seventh embodiment will be described usingthe first embodiment as a base. However, the invention is not limited tothe case. Obviously, the seventh embodiment can be applied to any of theforegoing embodiments and their modifications.

The rotation amount is generated or specified on the basis oforientation data in the rotation correcting unit 154 a of the imageprocessing unit 154. Therefore, in the medical system according to theseventh embodiment, the display device 150 (refer to FIG. 7) in themedical system 1 shown in FIG. 1 is replaced with a display device 750shown in FIG. 60. FIG. 60 is a block diagram showing a schematicconfiguration example of the display device 750 according to the seventhembodiment. As obvious from comparison between FIGS. 60 and 7, in thedisplay device 750, the image processing unit 154 in the display device150 is replaced with an image processing unit 754.

As shown in FIG. 60, the image processing unit 754 has a configurationsimilar to that of the image processing unit 154 except that a rotationamount indicator generating unit 754 a is added and the screengenerating unit 154 e is replaced with a screen generating unit (screengenerating means) 754 e. The rotation correcting unit 154 a according tothe seventh embodiment supplies the generated or specified rotationamount to the rotation amount indicator generating unit 754 a.

The rotation amount indicator generating unit 754 a is rotation amountimage generating means for generating an image (rotation amount image)visually displaying a rotation amount of each image data used at thetime of rotation correction. In the embodiment, the rotation amountindicator (refer to a rotation amount indicator 68 in FIG. 62) is usedas the rotation amount image. Therefore, the rotation amount indicatorgenerating unit 754 a generates an image of the rotation amountindicator using the input rotation amount and supplies the generatedimage to the screen generating unit 754 e.

The screen generating unit 754 e generates a GUI screen as shown in FIG.62 by using image data subjected to rotation correction which isselected by the image selecting unit 154 c, an image of the averagecolor bar supplied from the average color bar generating unit 154 d, andan image of the rotation amount indicator input from the rotation amountindicator generating unit 754 a. The GUI screen generated according tothe seventh embodiment will be described later.

Using FIG. 61, the operation of the display device 750 according to theseventh embodiment will be described in detail. As shown in FIG. 61,first, the display device 750 takes steps similar to the steps describedby using the steps S121 to S127 in FIG. 13 in the first embodiment,thereby executing the rotation correction on all of image data selected,and the process of generating an image of an average color bar. Next,the display device 750 executes a process of generating an image of arotation amount indicator from the rotation amount in the rotationamount indicator generating unit 754 a (step S721).

Next, the display device 750 makes the screen generating unit 754 eexecute the screen generating process for generating a GUI screen asshown in FIG. 62 by using the image data subjected to the rotationcorrection selected in the image selecting unit 154 c, the image of theaverage color bar supplied from the average color bar generating unit154 d, and an image of the rotation amount indicator supplied from therotation amount indicator generating unit 754 a (step S722) and, afterthat, finishes the process. The generated GUI screen is supplied to thedisplay unit 155 via the control unit 151 and displayed to the observer.As a result, the observer is provided with the GUI function using theGUI screen and the input unit 156.

Using FIG. 62, the GUI screen generated by the screen generating unit754 e will be described in detail. As shown in FIG. 62, in the GUIscreen generated by the screen generating unit 754 e, like the GUIscreen (refer to FIG. 8) generated by the screen generating unit 154 ein the foregoing embodiments, the patient information g11, the diagnosisinformation g12, the main image display region g13, the sub imagedisplay region g14, the reproduction control button g15, and the averagecolor bar 60 are incorporated. In the GUI screen, the rotation amountindicator 68 is also incorporated.

The length in the time base direction of the rotation amount indicator68 is the same as that of the average color bar 60, and the rotationamount indicator 68 is disposed above or below the average color bar 60in the screen. With the arrangement, the time base of the average colorbar 60 and that of the rotation amount indicator 68 can be linked inappearance, so that it enables the observer to easily recognize a regionin the capsule medical device 10 largely rotates, in the average colorbar 60.

The color in a region corresponding to each of image data pieces in therotation amount indicator 68 is graded according to the rotation amount.Consequently, the observer can easily recognize a region in which thecapsule medical device 10 largely rotates.

Modification 7-1

In the seventh embodiment, the case of visually displaying the rotationamount by using the rotation amount indicator 68 (refer to FIG. 62)expressing the rotation amount by a bar-shaped image has been describedas an example. The present invention is not limited to the case but, forexample, as shown in FIG. 63, the rotation amount may be superimposed onthe average color bar. FIG. 63 is a diagram showing an example of anaverage color bar 60_4 according to the modification 7-1 of the seventhembodiment. The average color bar 60_4 is obtained by superimposing animage expressing a rotation amount by a polygonal line in the averagecolor bar 60. Therefore, in the image of the rotation amount, as shownin FIG. 63, the rotation amount in each image data is expressed by theheight of the polygonal line. The invention, however, is not limited tothe expression. The rotation amount may be expressed by a histogram orthe like.

The rotation amount may be averaged by rotation amounts in apredetermined number of successive image data pieces. In the case wherethe averaging is not performed, the observer can know sharpness of achange in the rotation amount from an image of the polygonal line of therotation amount. In the case of performing the averaging, the observercan easily know the trend of a change in the rotation amount from theimage of the polygonal line of the rotation amount.

Eighth Embodiment

Next, an eighth embodiment will be described in detail with reference tothe drawings. In the following description, the eighth embodiment willbe described using the first embodiment as a base. However, theinvention is not limited to the description. Obviously, the eighthembodiment can be applied to any of the foregoing embodiments and theirmodifications.

The color and shape of the lumen in the subject 900 varies according toa region. The observer can recognize a region which is presentlydisplayed in the main image display region g13 in the GUI screen byvisually recognizing the average color bar 60 as shown in the foregoingembodiments (including their modifications). In the eighth embodiment,the GUI function enabling the observer can add an index of an arbitraryregion to the average color bar 60 is provided for the observer by usinga GUI screen (refer to FIG. 64) displayed in the display unit 155 andthe input unit 156. FIG. 64 is a diagram showing an example of the GUIscreen according to the eighth embodiment.

As shown in FIG. 64, in the GUI screen according to the eighthembodiment, like the GUI screen (refer to FIG. 8) according to the firstembodiment, the patient information g11, the diagnosis information g12,the main image display region g13, the sub image display region g14, andthe reproduction control button g15 are incorporated. In the embodiment,the average color bar 60 in FIG. 8 is replaced with the average colorbar 60_5. In the GUI screen according to the eighth embodiment, a box(region selection box g81) for selecting an index added to the positionof the slider g16 a in the average color bar 60_5, a box (sign box g82)for selecting a sign displaying the selected index, and a registrationbutton g83 for entering registration of the selected index and the signare incorporated.

The observer selects, as an index, a target region from a pulldown menuprovided in the region selection box g81. When any region is selected inthe region selection box g81, in the sign box g82, the sign to beselected next is automatically selected in accordance with apredetermined order. The observer can change a sign to be selected bythe pulldown menu provided in the sign box g82. The region selection boxg81 may be constructed to directly enter a character string. Further, asign may be designated in advance to an index selected in the regionselection box g81.

After selecting the name of the region and the sign in such a manner,the observer clicks the registration button g83. The display device 750enters the selected region and the sign as an index to the screengenerating unit 754 e in the image processing unit 754. The screengenerating unit 754 e adds the index to the average color bar 60_5 byusing the input name of the region and the sign, generates an image forvisually displaying the index (particularly, the sign), and adds theimage to a corresponding part in the average color bar 60_5. The GUIscreen in which the image of the index is added to the average color bar60_5 is supplied to the display unit 155 and displayed to the observer.As a result, in the corresponding part in the average color bar 60_5, asshown in FIG. 64, the sign (for example, “a” to “e”) indicating that theindex is added is displayed. Consequently, the observer can easily knowthe region whose image data is presently displayed in the main imagedisplay region g13.

In the GUI screen according to the eighth embodiment, an image of thelumen in the subject 900 (hereinbelow, called organ image) g84 isincorporated. In the case where the subject 900 is a human, regions suchas pylorus, appendix, hepatic flexure, splenic flexure, colon sigmoid,and the like do not depend on individuals but are almost the same in allof the subjects 900.

In the eighth embodiment, the organ image g84 is formed as an image ofthe general subject 900, and the position of the region in an imagedrawn by the organ image g84 is defined in advance. When the observerselects a region by using the region selection box g81 in the GUI screenshown in FIG. 64, an image (color, texture, or the like) of a regionsandwiched by the region selected in the average color bar 60_5 and theregion selected before is adhered to a corresponding interval in thelumen shape in the organ image g84. In the case where there is no imageselected before, images (colors, textures, or the like) from the head toa corresponding region in the time base of the average color bar 60_5are adhered to the organ image g84.

By the operation as described above, display similar to the averagecolor bar 60_5 can be superimposed on the organ image g84 in the GUIscreen according to the embodiment. As a result, the observer can easilyrecognize an average color in a region.

In the eighth embodiment, an index to be added to the average color bar60_5 is selected/entered manually. However, the invention is not limitedto the case. For example, a region may be automatically specified fromthe color or the like of the average color bar 60_5 and added as anindex to the average color bar 60_5.

Modification 8-1

The rotation amount and a change rate of the rotation amount of acapsule medical device introduced in the subject 900 change according tothe shape of a lumen through which the device passes, that is, theregion as shown in FIG. 65. FIG. 65 is a diagram showing the relationbetween the region in the lumen 902 through which the capsule medicaldevice 10 introduced in the subject 900 passes and the rotation amount.

The region can be automatically specified on the basis of changes in therotation amount and the change rate and added as an index to the averagecolor bar 60_5. In the following, the case will be described in detailas modification 8-1 of the eighth embodiment with reference to thedrawings. In the following description, the modification 8-1 will bedescribed using the eighth embodiment as a base. However, the inventionis not limited to the case. Obviously, the modification 8-1 can beapplied to any of the foregoing embodiments and their modifications.

In a medical system according to the modification 8-1, the displaydevice 150 (refer to FIG. 7) in the medical system 1 shown in FIG. 1cited in the eighth embodiment is replaced with a display device 850shown in FIG. 66. FIG. 66 is a block diagram showing a schematicconfiguration example of the display device 850 according to themodification 8-1. As obvious from comparison between FIG. 66 and FIG. 7,in the display device 850, the image processing unit 154 in the displaydevice 150 is replaced with an image processing unit 854.

As shown in FIG. 66, the image processing unit 854 has a configurationsimilar to that of the image processing unit 154 except that an organdetermining unit (organ determining means) 854 a and an organ imagegenerating unit (organ image generating unit) 854 b are added and thescreen generating unit 154 e is replaced with a screen generating unit(screen generating means) 854 e. The rotation correcting unit 154 aaccording to the modification 8-1 enters the generated or specifiedrotation amount to the organ determining unit 854 a. The average colorbar generating unit 154 d enters the data of the average color in theregions generated to the organ image generating unit 854 b.

The organ determining unit 854 a functions as organ determining meansfor determining an organ positioned near the capsule medical device 10when image data is obtained on the basis of the rotation amount of eachimage data used for rotation correction, and specifies image data at atiming when the capsule medical device 10 passes through each of theorgans (for example, pylorus 907 a, appendix 907 b, hepatic flexure 907c, splenic flexure 907 d, colon sigmoid 907 e, and the like) from theinput rotation amount and the change rate. The rotation amount isgenerated for each image data which is associated with each other.

The organ determining unit 854 a specifies an image of an average colorbar corresponding to a path between the organs from the image data (itsID) of each organ specified and an image of the average color barentered from the average color bar generating unit 154 d, and suppliesthe specified result to the organ image generating unit 854 b. The imageof the average color bar is obtained by connecting images of the averagecolors of image data pieces. With the image of the average color ofimage data, the ID of the corresponding image data is associated.

The organ image generating unit 854 b matches the organ imagepreliminarily generated and the index added to the organ image with aspecification result entered from the organ determining unit 854 a,specifies data of the average color in the corresponding regions to theorgan image of the regions matched, and adheres it to the organ image.In such a manner, an organ image similar to the organ image g84 in theGUI screen illustrated in FIG. 64 is automatically generated.

Modification 8-2

On the organ image g84, not only an image of the average color but a reddetection result may be also superimposed as shown in an organ imageg84B incorporated in a GUI screen according to modification 8-2 of theeighth embodiment shown in FIG. 67.

Since an image processing unit which generates the organ image g84B canbe easily reached from the image processing unit 654 shown in FIG. 54and the image processing unit 854 shown in FIG. 66, its detaileddescription will not be given here. In the GUI screen shown in FIG. 67,the red indicator 66 is also incorporated.

Modification 8-3

Further, in the GUI screen (refer to FIG. 64) according to theembodiment, as shown in a GUI screen according to modification 8-3 shownin FIG. 68, for example, the rotation amount indicator 68 may beincorporated.

Ninth Embodiment

More concrete description of the image selecting unit 154 c in theforegoing embodiments (including their modifications) will be givenbelow as a ninth embodiment with reference to drawings. FIG. 69 is ablock diagram showing a schematic configuration example of the imageselecting unit 154 c according to the ninth embodiment.

As shown in FIG. 69, the image selecting unit 154 c includes a buffer954 b for temporarily holding an image subjected to rotation correctionwhich is entered last time, a similarity determining unit 954 a fordetermining similarity of image data of this time to immediatelypreceding image data from an image subjected to rotation correctionwhich is entered this time and an image subjected to rotation correctionof last time which is held in the buffer 954 b, and a unit 954 c forselecting an image to be displayed, which selects image data subjectedto rotation correction on the basis of the determination of thesimilarity by the similarity determining unit 954 a.

The similarity determining unit 954 a functions as similaritydetermining means for determining similarity between successive imagedata in a plurality of pieces of image data subjected to rotationcorrection. The similarity determining unit 954 a obtains the differencebetween color component values pixel by pixel in the same position inimage data subjected to rotation correction of last time read from thebuffer 954 b and image data subjected to rotation correction of thistime, and obtains the sum of the differences of the color componentvalues derived pixel by pixel in the entire screen. In the case wherethe sum of the differences of the color component values in the entirescreen is smaller than a predetermined threshold, it is determined thatthe image data subjected to rotation correction of this time is imagedata similar to the image data subjected to rotation correction of lasttime, that is, image data of the same region. The determination resultis supplied to the unit 954 c of selecting an image to be displayed. Onthe other hand, in the case where the sum of the differences of thecolor component values in the entire screen of the image data subjectedto rotation correction of last time and image data subjected to rotationcorrection of this time is equal to or larger than the predeterminedthreshold, it is determined that the image data subjected to rotationcorrection of this time is image data different from the image datasubjected to rotation correction of last time, that is, image data of adifferent region. The determination result is supplied to the unit 954 cof selecting an image to be displayed.

The unit 954 c of selecting an image to be displayed functions as imagedata selecting means for selecting image data subjected to rotationcorrection and satisfying a predetermined condition from a plurality ofpieces of image data subjected to rotation correction on the basis ofthe determination result of the similarity determining unit 954 a. Inthe case where the determination result supplied from the similaritydetermining unit 954 a indicates that image data subjected to rotationcorrection of this time is image data of a region different from that ofimage data subjected to rotation correction of last time, the unit 954 cof selecting an image to be displayed selects the image data. That is,the image data is supplied to the average color bar generating unit 154d and the screen generating unit 154 e. On the other hand, in the casewhere the determination result supplied from the similarity determiningunit 954 a indicates that image data subjected to rotation correction ofthis time is image data of the same region as that the image datasubjected to rotation correction of last time, the unit 954 c ofselecting an image to be displayed discards the image data subjected torotation correction of this time.

By constructing the image selecting unit 154 c as described above, inthe ninth embodiment, image data subjected to rotation correction of aregion different from that of the image data subjected to rotationcorrection of last time can be preferentially selected and displayed. Asa result, a number of image data pieces of the same region can beprevented from being continuously displayed, so that the observer canread the images more efficiently.In the embodiment, by adjusting a threshold used at the time ofdetermining similarity of successive images, the number of pieces ofimage data to be selected can be adjusted. As a result, the reproductionspeed can be also adjusted.

Tenth Embodiment

The screen generating unit (154 e, 654 e, 754 e, or 854 e) in any of theforegoing embodiments (including their modifications) may form thumbnailimages of image data subjected to rotation correction which is selectedby the image selecting unit 154 c and display a list of the images asshown in a GUI screen according to a tenth embodiment of FIG. 70 (alsocalled “overview display”). That is, the screen generating unit 154 e inthe display device 150 may reduce the selected image data subjected torotation correction and generate a GUI screen (refer to FIG. 70)displaying a list of reduced images.

Eleventh Embodiment

Another form of the display device 150 in any of the foregoingembodiments (including their modifications) will be described in detailbelow as an eleventh embodiment with reference to the drawings. FIG. 71is a block diagram showing a schematic configuration example of adisplay device 1150 according to the eleventh embodiment. In thefollowing description, the eleventh embodiment will be described usingthe first embodiment as a base. However, the invention is not limited tothe case. Obviously, the eleventh embodiment can be applied to any ofthe foregoing embodiments and their modifications.

As shown in FIG. 71, the display device 1150 has a configuration similarto that of the display device 150 shown in FIG. 7 except that the imageprocessing unit 154 is replaced with an image processing unit 1154.

As shown in FIG. 71, the image processing unit 1154 has a configurationsimilar to that of the image processing unit 154 except that the featurepoint extracting unit 154 b is replaced with a motion vector calculatingunit 1154 b, and the image selecting unit 154 c is replaced with animage selecting unit 1154 c.

The motion vector calculating unit 1154 b functions as motion vectorcalculating means for calculating a motion vector between successiveimage data in a plurality of pieces of image data subjected to rotationcorrection, calculates a motion vector in a region in the successiveimage data, and supplies the motion vector to the image selecting unit1154 c. The image selecting unit 1154 c includes a maximum scalarquantity extracting unit 1154 d (maximum scalar quantity extractingmeans) for extracting a value at which a scalar quantity is maximum inthe motion vectors supplied from the motion vector calculating unit 1154b. The image selecting unit 1154 c functions as image data selectingmeans for selecting image data subjected to the rotation correction andsatisfying a predetermined condition, from a plurality of pieces ofimage data subjected to the rotation correction on the basis of a resultof extraction by the maximum scalar quantity extracting unit 1154 d.

For example, in the case where the maximum scalar quantity of the motionvector extracted by the maximum scalar quantity extracting unit 1154 dis equal to or less than a predetermined threshold, the image selectingunit 1154 c determines that image data of last time and image data ofthis time are captured from different regions and selects the image dataof this time. That is, the image data is supplied to the average colorbar generating unit 154 d and the screen generating unit 154 e. On theother hand, in the case where the maximum scalar amount of the motionvector extracted by the maximum scalar quantity extracting unit 1154 dis larger than a predetermined threshold, the image selecting unit 1154c determines that image data of last time and image data of this timeare captured from the same region and discards the image data of thistime.

By constructing the image selecting unit 1154 c as described above, inthe eleventh embodiment, the image data subjected to rotation correctionof a region different from that of the image data subjected to rotationcorrection of last time can be preferentially selected and displayed. Asa result, a number of image data pieces of the same region can beprevented from being continuously displayed, so that the observer canread the images more efficiently.

In the embodiment, by adjusting a threshold used at the time ofdetermining similarity of successive images, the number of pieces ofimage data to be selected can be adjusted. As a result, the reproductionspeed can be also adjusted.

Twelfth Embodiment

Another form of the display device 150 or 1150 in any of the foregoingembodiments (including their modifications) will be described in detailbelow as a twelfth embodiment with reference to the drawings. FIG. 72 isa block diagram showing a schematic configuration example of a displaydevice 1250 according to the twelfth embodiment. In the followingdescription, the twelfth embodiment will be described using the firstand eighth embodiments as a base. However, the invention is not limitedto the case. Obviously, the twelfth embodiment can be applied to any ofthe foregoing embodiments and their modifications.

As shown in FIG. 72, the display device 1250 has, in addition to aconfiguration similar to that of the display device 150 shown in FIG. 7,a position/movement path estimating unit 1257. In the twelfthembodiment, the image data subjected to rotation correction by therotation correcting unit 154 a in the image processing unit 154 is alsosupplied to the position/movement path estimating unit 1257.

The position/movement path estimating unit 1257 functions as positionestimating means for estimating the position of the capsule medicaldevice 10 at the time of obtaining image data on the basis of therotation amount used for rotation correction on each image data, andincludes a similarity calculating unit 1257 a for calculating similarityof image data successively supplied from the rotation correcting unit154 a, a movement distance estimating unit 1257 b for estimating adistance of movement of the capsule medical device 10 during imaging thesuccessive image data on the basis of the similarity calculated by thesimilarity calculating unit 1257 a, and a position/path estimating unit1257 c for estimating the position and a movement path of the capsulemedical device 10 at the time of capturing image data of this time onthe basis of the movement distance estimated by the movement distanceestimating unit 1257 b.

The image data subjected to rotation correction which is supplied fromthe rotation correcting unit 154 a to the position/movement pathestimating unit 1257 is supplied to the similarity calculating unit 1257a. The similarity calculating unit 1257 a calculates similarity ofsuccessive image data in the input image data subjected to rotationcorrection and supplies the calculated similarity to the movementdistance estimating unit 1257 b. The similarity of successive image datacan be calculated from, for example, a feature point, a motion vector,or the like of the image data.

The movement distance estimating unit 1257 b estimates a distance ofmovement of the capsule medical device 10 at the time of capturing thesuccessive image data on the basis of the input similarity and suppliesthe estimated movement distance to a position/path estimating unit 1257c. The movement distance can be estimated on the basis of, for example,a corresponding relation between similarity and distance which isobtained in advance by experiment, experience, simulation, or the like.

The position/path estimating unit 1257 c estimates the position andmovement path of the capsule medical device 10 at the time of capturingthe image data of this time on the basis of the input movement distanceand the position and the movement path of the capsule medical device 10at the time of capturing image data of last time estimated last time,and supplies them to the screen generating unit 154 e in the imageprocessing unit 154. To the position/path estimating unit 1257 c,information on the position and the movement path of the capsule medicaldevice 10 may be separately supplied from the control unit 151 or thelike. In the case where the information on the position and the movementpath of the capsule medical device 10 is supplied separately, theposition/path estimating unit 1257 c corrects an error in the positionand the movement path of the capsule medical device 10 estimated asdescribed above, with the position and the movement path suppliedseparately. The error correction can be executed by, for example, aconvergence calculation by iterative operation using the least squaremethod.

The position and the movement path at each of the imaging timings of thecapsule medical device 10 estimated by the position/movement pathestimating unit 1257 are supplied to, for example, the screen generatingunit 154 e in the image processing unit 154. The screen generating unit154 e generates, for example, a GUI screen as shown in FIG. 73 by usingthe position and the movement path of the capsule medical device 10 ateach of the imaging timings. The GUI screen shown in FIG. 73 is obtainedby, for example, applying the embodiment to the GUI screen according tothe eighth embodiment.

As shown in the GUI screen of FIG. 73, in the twelfth embodiment, amarker g121 indicative of the position of the capsule medical device 10at the timing of capturing the image data being displayed in the mainimage display region g13 and a path g122 of movement of the capsulemedical device 10 until the image data is captured are superimposed onthe organ image g84. With the image, the observer can easily know theposition of the capsule medical device 10 and the movement locus untilthen at the time of capturing the image data being displayed from theorgan image g84.

According to the embodiments, the orientations of a plurality of imagedata pieces can be aligned by performing rotation correction on imagedata on the basis of the orientation with reference to the referencedirection of the body-insertable apparatus at the time of imaging, sothat the image processing system, the external device of the same, andthe image processing method realizing reduced time and labor at the timeof diagnosis and improved accuracy of a diagnosis result can berealized.

The foregoing embodiments are just examples for carrying out the presentinvention. The invention is not limited to the embodiments. Obviously,various modifications according to specifications and the like are inthe scope of the present invention. It is obvious from the abovedescription that other various embodiments are possible within the scopeof the invention.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

1. An image processing system comprising: a body-insertable apparatusincluding an imaging unit that captures inside of a subject and anoutput unit that outputs image data obtained by the imaging unit to theoutside; and an external device including an input unit that receivesthe image data, a first orientation specifying unit that specifiesorientation of the body-insertable apparatus at the time of capturingthe image data with respect to a reference direction, a rotationcorrecting unit that performs rotation correction on image data which isreceived by the input unit based on the orientation specified by thefirst orientation specifying unit, thereby aligning orientations of aplurality of pieces of image data, a screen generating unit thatgenerates a screen displaying the image data subjected to the rotationcorrection in the rotation correcting unit, and a rotation amount imagegenerating unit that generates a rotation amount image visuallydisplaying a rotation amount used for the rotation correction for eachof the image data, wherein the screen generating unit generates thescreen in which the rotation amount image generated by the rotationamount image generating unit is incorporated.
 2. The image processingsystem according to claim 1, wherein the first orientation specifyingunit specifies orientation of the body-insertable apparatus usingorientation of the subject as a reference.
 3. The image processingsystem according to claim 1, wherein the first orientation specifyingunit obtains orientation of the body-insertable apparatus using a realspace as a reference.
 4. The image processing system according to claim1, wherein the external device further includes a directional antennahaving directivity and an electromagnetic wave transmitting unit thattransmits an electromagnetic wave via the directional antenna, thebody-insertable apparatus further includes a plurality of antennas and astrength/phase detecting unit that detects strength and phase of theelectromagnetic wave received by each antenna, the output unit adds thestrength and phase of the electromagnetic wave detected by thestrength/phase detecting unit to the image data and outputs theresultant data to the outside, the input unit supplies the strength andphase of the electromagnetic wave added to the image data to the firstorientation specifying unit, and the first orientation specifying unitspecifies the orientation of the body-insertable apparatus from thestrength and phase of the electromagnetic wave supplied from the inputunit.
 5. The image processing system according to claim 4, wherein theexternal device further includes a second orientation specifying unitthat specifies orientation of the subject, the reference direction isset for the subject, and the first orientation specifying unit performsrotation correction on the orientation of the body-insertable apparatuswith respect to the specified reference direction with the orientationof the subject specified by the second orientation specifying unit. 6.The image processing system according to claim 1, wherein thebody-insertable apparatus further includes a gravity direction detectingunit that detects a direction of gravity, the output unit adds thedirection of gravity detected by the gravity direction detecting unit tothe image data and outputs the resultant data to the outside, the inputunit supplies the direction of gravity added to the image data to thefirst orientation specifying unit, and the first orientation specifyingunit specifies orientation of the body-insertable apparatus from thedirection of gravity supplied from the input unit.
 7. The imageprocessing system according to claim 1, the external device furtherincludes an average color bar generating unit that calculates an averagecolor of the image data subjected to the rotation correction in therotation correcting unit, generates an image of the calculated averagecolor, and generates an average color bar in which images of thegenerated average colors are connected in accordance with order of theimage data, wherein the screen generating unit generates the screen inwhich the average color bar generated by the average color bargenerating unit is incorporated.
 8. The image processing systemaccording to claim 7, wherein the average color bar generating unitcalculates the average color in each of division regions obtained bydividing one piece of the image data, generates an image of the averagecolor for each of the divided regions, and generates the average colorbar so that images of the average color for corresponding divisioncolors in the image data are arranged in parallel to a predeterminedaxis.
 9. The image processing system according to claim 1, wherein theexternal device further includes a red detecting unit that detects a redcomponent included in the image data subjected to the rotationcorrection; and a red image generating unit that generates a red imagevisually displaying a detection result of the red detecting unit, andthe screen generating unit generates the screen in which the red imagegenerated by the red image generating unit is incorporated.
 10. Theimage processing system according to claim 1, wherein the externaldevice further includes an organ image generating unit that generates animage of an organ in the subject, and the screen generating unitincorporates the organ image in the screen.
 11. The image processingsystem according to claim 7, wherein the external device furtherincludes an organ image generating unit that generates an organ image,as an image of an organ in the subject, obtained by superimposing imagesof the average color generated by the average color bar generating unit,and the screen generating unit incorporates the organ image in thescreen.
 12. The image processing system according to claim 9, whereinthe external device further includes an organ image generating unit thatgenerates an organ image as an image of an organ in the subject,obtained by superimposing images of the detection results generated bythe red image generating unit, and the screen generating unitincorporates the organ image in the screen.
 13. The image processingsystem according to claim 1, wherein the external device furtherincludes a position estimating unit that estimates position of thebody-insertable apparatus at the time of obtaining the image data basedon the rotation amount used for the rotation correction for each imagedata.
 14. The image processing system according to claim 1, wherein theexternal device further includes a similarity determining unit thatdetermines similarity of successive image data in a plurality of piecesof image data subjected to the rotation correction; and an image dataselecting unit that selects image data subjected to the rotationcorrection, satisfying a predetermined condition from the plurality ofpieces of image data subjected to the rotation correction based on aresult of determination by the similarity determining unit.
 15. Theimage processing system according to claim 1, wherein the externaldevice further includes a motion vector calculating unit that calculatesmotion vectors of successive image data in the plurality of pieces ofimage data subjected to the rotation correction; a maximum scalarquantity extracting unit that extracts a value at which a scalarquantity is maximum in the motion vectors calculated by the motionvector calculating unit; and an image data selecting unit that selectsimage data subjected to the rotation correction, satisfying apredetermined condition, from a plurality of pieces of image datasubjected to the rotation correction based on a result of extraction bythe maximum scalar quantity extracting unit.
 16. The image processingsystem according to claim 1, wherein the screen generating unitgenerates a screen displaying a list of reduction images obtained byreducing the image data subjected to the rotation correction.
 17. Anexternal device comprising: an input unit that receives image dataobtained by a body-insertable apparatus including an imaging unit thatcaptures inside of a subject; an orientation specifying unit thatspecifies orientation of the body-insertable apparatus at the time ofcapturing the image data with respect to a reference direction; arotation correcting unit that performs rotation correction on image datawhich is received by the input unit on the basis of the orientationspecified by the orientation specifying unit, thereby aligningorientations of a plurality of pieces of image data; a screen generatingunit that generates a screen displaying the image data subjected to therotation correction in the rotation correcting unit; and a rotationamount image generating unit that generates a rotation amount imagevisually displaying a rotation amount used for the rotation correctionfor each of the image data, wherein the screen generating unit generatesthe screen in which the rotation amount image generated by the rotationamount image generating unit is incorporated.
 18. An image processingmethod comprising: receiving image data obtained by a body-insertableapparatus including an imaging unit that captures inside of a subject;specifying orientation of the body-insertable apparatus at the time ofcapturing the image data with respect to a reference direction;performing rotation correction on image data which is received by theinput unit on the basis of the specified orientation, thereby aligningorientations of a plurality of pieces of image data; generating a screendisplaying the image data subjected to the rotation correction; andgenerating a rotation amount image visually displaying a rotation amountused for the rotation correction for each of the image data, wherein thegenerating the screen includes generating the screen in which thegenerated rotation amount image is incorporated.
 19. An image processingsystem comprising: a body-insertable apparatus including an imagingmeans for capturing inside of a subject and an output means foroutputting image data obtained by the imaging means to the outside; andan external device including an input means for receiving the imagedata, an orientation specifying means for specifying orientation of thebody-insertable apparatus at the time of capturing g the image data withrespect to a reference direction, a rotation correcting means forperforming rotation correction on image data received by the input meansbased on the orientation specified by the orientation specifying means,thereby aligning orientations of a plurality of pieces of image data, ascreen generating means for generating a screen displaying the imagedata subjected to the rotation correction in the rotation correctingmeans, and a rotation amount image generating means for generating arotation amount image visually displaying a rotation amount used for therotation correction for each of the image data, wherein the screengenerating means generates the screen in which the rotation amount imagegenerated by the rotation amount image generating means is incorporated.